Hyoudou Residence
Early Saturday Morning
It was the morning after Issei met with the Greeks; when he woke up, he groaned in annoyance, knowing he had to spend time with Rias when he could've done something more productive. Now, he was in his old house, inside Rias's room; he was standing over the sleeping form of a naked Rias, whose crimson hair sprawled over her, sleeping without a care in the world.
Issei looked down at Rias with an annoyed expression and scowled, not amused by her tardiness. There was an air horn in his hand, its muzzle facing towards Rias. He pressed the button, and a loud, blaring noise filled the room, jolting Rias awake with a scream. She sat up quickly, her eyes wide and her hair even more dishevelled than before.
Rias then looked toward the loud noise, thinking Akeno was playing a prank on her. But she saw a taller, more robust figure dressed in a black and grey tracksuit. As her eyes travelled up to the face of the person, she saw impassive silver eyes staring down at her; Rias gulped a bit, realising it was Issei before her irritation returned.
"Issei! What the hell?" Rias yelled; her face was a mix of anger and confusion as she wiped the grim from her eyes.
Issei crossed his arms, the air horn still in hand. "You've got training this morning, remember? We don't have time for you to laze around," he says sternly.
He pushes the muzzle of the air horn close to Rias's face. "So I suggest putting on suitable clothes", he continues as he presses the button on the air horn once more.
Rias winced and flinched back at the loud noise, her irritation boiling over. "Alright, alright! I'm getting up, geez!" she snapped, her cheeks flushing in embarrassment and frustration.
Issei watched her for a moment longer before turning his back, giving her some semblance of privacy. "I'll be waiting outside. Don't take too long," he said flatly, leaving the room and closing the door behind him.
Rias grumbled under her breath, rubbing her ears as she reluctantly climbed out of bed. She quickly grabbed her training outfit and dressed, the irritation still simmering.
A few minutes later, she exited her room, fully dressed in her gear. Issei was leaning against the wall, arms still crossed and expression unchanged. He pushed off the wall and stretched his hand out.
[Ability Used: Rift]
A rip in time and space formed before him; he turned his head back to Rias. "After you," he says as he gestures for Rias to enter the portal.
Rias nods slowly before stepping through the portal, followed by Issei. As she stepped out from the other side, she found herself in a large gym with various equipment. The gym had two floors, which overlooked the ground floor.
Rias looked around in awe. When she was here a week ago, she remembered the entire place. "Issei, did you recently renovate your castle?" she asked, turning to Issei behind her.
Issei closed the portal behind him before answering, "I did".
Rias nodded in understanding before looking around at the expansive gym. "So what will I do first?" she asked, eying the different equipment; in the corner, she saw a rock climbing wall going up by 30 meters and hoped Issei would let her do that.
Issei eyed Rias with a calculating gaze; he could feel her anticipation for the rock climbing wall. "We'll start with a small warmup", he starts as he points to a running track towards the end of the gym. "We'll go for a 45-minute run."
Rias groaned inwardly but nodded. She knew better than to argue with Issei when it came to training. "Fine," she muttered, making her way to the track.
Issei followed her, his expression still stern. "I expect you to give it your all," he said as they reached the starting line. "No slacking off. We'll increase the intensity as we go."
Rias rolled her eyes but kept her mouth shut. She started running, keeping a steady pace. Issei ran beside her, his strides effortless and smooth. After the first ten minutes, Issei began to increase the pace gradually. Rias struggled to keep up but pushed herself, her competitive spirit kicking in. She refused to let him see her weakness.
After the first twenty seconds, Rias could no longer keep up with Issei, allowing him to lap her multiple times. This act overall lowered Rias's morale. Each time she got lapped, anger and shame washed over her. On the other hand, Issei was conversing with Ddraig, not noticing Rias's feelings.
"Remember when I said I wanted to replicate Vali's compression divider ability into one of my own?" Issei asked Ddraig.
Ddraig hummed in acknowledgement, "Indeed, you wanted to increase the size of your opponent's organs to cause biological destruction", he replied.
Issei nodded, "Yes, I was also thinking, what about continuously doubling the size of molecules and atoms entirely within an opponent?" he elaborates.
Ddraig's tone became thoughtful, "Yes, it could work on opponents who aren't biological entities, unlike the previous idea. What do you plan on naming it?" he asked.
Issei sighed, "Not sure..." he replied as he continued to run.
As his attention shifted back to the track he was running on, he saw he was about to lap Rias again. As he approached, he decided to get a little payback.
"Has anyone ever told you; you run like a schoolgirl?" he spoke as he lapped Rias again.
Rias's cheeks flushed with embarrassment and anger at Issei's remark. She remembered she told Issei those words when she made him run when he first became a devil under her care.
She clenched her fists and picked up her pace, determined not to let him get to her. "Shut up, Issei," she snapped back, gritting her teeth.
Issei smirked, satisfied with her reaction. "The circle is now complete. When I left you, I was but the learner; now I am the master." he thought, reciting a certain sand-hating dark lord's words.
After the forty-five minutes of running, Rias was drenched in sweat, her breathing heavy, and her legs burning from the exertion. Issei, on the other hand, seemed barely winded.
Issei looked at the huffing and puffing Rias; he then remembered Rias made him do push-ups while she sat on his back when he first became a Devil. And so he decided to bully Rias a bit more.
Issei motioned for Rias to follow him to a clear area with mats laid out on the floor. "Alright, time for some push-ups," he announced.
Rias groaned, already feeling the strain in her muscles. She got down into position, ready to start.
Issei smirked as he walked over and sat on her back, just as she had done to him in the past. "Let's see how many you can do with some extra weight," he said, a hint of amusement in his voice.
Rias struggled to push herself up, her arms shaking under Issei's weight. She managed to do a few push-ups before collapsing onto the mat, panting heavily.
Issei got up and shook his head. "Pathetic. You need to build more strength," he said, his tone stern.
Rias glared up at him, her pride wounded. "How... heavy are you?" she muttered in an exhausted tone; she knew he had to be over 100kgs at least due to Issei's build.
"140kgs", Issei answered casually as if it were every day.
Rias's eyes widened in disbelief, her breath still coming in short gasps. "140 kgs...?" she repeated, incredulous. "You weigh more than two of me!". She compared Sairaorg to Issei since the two had a similar build, although Issei was slimmer at his waist and leaner.
"Sairaorg is only 135kgs; the two of you are similar in build; how are you 5kgs heavier?" she asked disbelievingly.
Issei shrugged, "I guess I have heavier bones... and my legs are more built than his." he replied, not really caring to elaborate. "Then again, my muscle density is something else..." he thought.
Rias got up, realising that Issei didn't care about explaining himself. As she did, Issei handed over a bottle of chilled water. Rias smiled a bit, taking a bottle from Issei's hand.
"Thank you, Issei. Although flavoured milk would've been nice." she thanked, referring to having the various flavoured milk in the training room in the Hyoudou Residence.
Issei scowled, "Are you a child?" he asked in a peeved tone.
Rias took a sip of the water, her cheeks flushing slightly. "No, but it's nice to have a treat after a tough workout," she muttered defensively, wiping the sweat from her forehead.
Issei had an unimpressed look, "A treat?" he muttered to himself as he drank from his own water bottle.
As he drank, he observed Rias taking the water; as she did, he saw the fatigue from the previous workout drain from her body.
"As I thought, the water on this planet is much more specialised than the water from Earth. I thought only I could reap the benefits, but it seems that others can too," Issei thought.
In Issei's section of his planet, he had a facility to collect the ocean's water and filter it into a consumable liquid. However, the process was useless as the ocean water was distilled enough to drink from. Issei discovered that the water had unique properties, such as revitalising the consumer and ridding the body of impurities such as dead skin, blackheads, acne, etc.
After gulping down the water from the bottle, Rias let out a satisfied sigh. "I've never had such refreshing water... Issei, where did you get this?" she asked, hoping she could buy a ton for herself.
Issei looked impassive, "It's from this planet; this Castle isn't the only thing that was remodelled. I turned this entire dimension into a planet. The water you are drinking is the natural ocean water", he replied.
Rias's eyes widened in surprise. "You turned this dimension into a planet?" she repeated, incredulity evident in her voice. "How did you even manage that?"
Issei shrugged nonchalantly. "It wasn't that difficult," he said. "I used my abilities to shape the dimension, and over time, it evolved into a planet. The water, the environment, everything here is a result of that process."
Rias stared at him, a mixture of awe and disbelief on her face. "You really are something else, Issei," she muttered, shaking her head slightly. "I can't even begin to imagine the power it takes to do something like that."
Issei didn't respond immediately, "It is my personal dimension, after all; it only makes sense for me to have some level of omnipotency..." he replied. "... anyways, now that the warmup is done, let's get to the main training."
X
Issei and Rias were now in a wasteland; Issei had commanded the elemental sprites to build a large city as a target practice. Now, he was watching Rias unleash her power of destruction on the buildings.
The buildings in the range of the blast were obliterated entirely by Rias's attacks. Issei watched on the sidelines, but instead of watching the destruction, he watched the energy in Rias's body.
Rias unleashed one final attack, putting her all into it. As the destructive energy hit the range, a few city blocks were destroyed instantly. Rias instantly grasped her knees for support as she bent over slightly; she looked over to Issei, hoping her display would've impressed him.
"So, how did I do?" she asked through batted breath.
Issei took a moment, "Horrendous", he replied curtly, causing Rias to flinch.
Rias's shoulders slumped at Issei's harsh critique. "Horrendous?" she repeated, her voice tinged with disbelief and hurt. "I put everything into that!"
Issei walked over to her, his expression still stern. "Your control over your ability is pathetic," he said bluntly. "You waste too much energy on each attack, and the way the energy flows through your body is atrocious. What good are you if you get winded on a few subpar attacks? It's a wonder how you've survived this long."
Rias felt a sharp sting at Issei's words, her frustration and determination blending into a burning resolve. "Then show me," she challenged her voice firm despite the hurt. "Show me how to control it better."
Issei's expression didn't soften, "That last attack of yours, I'll use the exact amount of energy you used", he explained as he raised his palm towards the testing range.
[Ability Used: Energy Manipulation: Energy Generation]
A black and red ball of energy appeared on the palm of Issei's hand, sparks flying off it. Issei then released the energy ball, which sped into the city and exploded on contact, causing the entire testing range to be obliterated instantly.
Rias's mouth dropped at the size and destruction of the explosion; if Issei hadn't said he used the exact amount of energy she did, she would've assumed that he used more.
"Woah..." she muttered in awe.
Issei turned back to Rias, his expression still stern. "When I use my abilities, I use the most efficient amount of energy to perform my abilities. Just now, I matched your energy usage, meaning that if we were to replicate the destructive potential of your attacks, then I'd need to lower my output," he explains.
"My control over my energy expenditure goes down to the quantum level. Meaning that not a single energy is wasted when I unleash my abilities." he continues.
Rias's eyes widened as she absorbed Issei's explanation. "Down to the quantum level?" she repeated, a mix of awe and intimidation in her voice.
Issei nodded, "Yes, I achieve such levels through my mastery over cultivating the energy in my body."
Rias raised an eyebrow, "Cultivating?" she asked for confirmation.
Issei nodded, his expression still stern but with a hint of patience in his eyes. "Yes, cultivating. It's the practice of refining and enhancing the energy within your body to achieve greater control and efficiency. It requires intense focus and discipline."
Rias listened intently, absorbing his words. "How do I start?" she asked, determination flickering in her eyes.
Issei gave a slight nod of approval. "The first step is to understand your own energy. Sit down and close your eyes," he instructed.
Rias did as she was told, sitting cross-legged on the ground and closing her eyes. Issei knelt in front of her, his voice steady and guiding.
"Focus on your breathing," he began. "Inhale deeply and exhale slowly. Feel the energy flowing through your body with each breath."
Rias concentrated, following his instructions. She took deep, measured breaths, trying to sense the energy flow within her. At first, it was difficult, her mind wandering to her frustrations and doubts, but she pushed those thoughts aside and focused solely on her breathing.
"Now," Issei continued, "visualise the energy as a stream of light flowing through your body. Feel it moving from your core to your extremities, filling every part of you."
Uncertainty came over Rias from Issei's terminology, "Core?" she asked for clarification.
"Your lower back, dead centre, well... more precisely, imagine if there was a belly button on your back that is parallel to the one on your front," Issei answered. "That's where the energy in your body should generate from and spread throughout your entire body."
Rias nodded slightly, digesting Issei's explanation. She focused again, imagining a point in her lower back where energy originated. As she concentrated, she felt a faint warmth in that area, spreading gradually through her body like a gentle current.
"Good," Issei said, noticing the subtle shift in her energy. "Now, try to control the flow. Guide it with your mind, directing it to your limbs and back to your core. Feel how it moves, how it responds to your thoughts."
Rias focused intently, visualising the stream of energy as it travelled through her body. At first, it was erratic and difficult to control, but she gained more confidence with each breath. She could feel the energy responding to her will, becoming more fluid and manageable.
"That's it," Issei encouraged. "Keep refining that control. Once you can direct the energy smoothly, you'll need to practice condensing it, making it denser and more powerful without increasing the amount used."
Rias opened her eyes, "I can feel it," she said, her voice filled with newfound confidence. "It's faint, but I can feel the energy moving. But, I would find it quite tedious when in battle."
Issei nodded in understanding, "At first, yes, but eventually, you will reach a point where cultivating is second nature as breathing", he explained. "For me, I passively do it. When you watch me fight, you never see an outline of my energy around my body, like with everyone else. That is because the energy is being generated from within. Doing it has numerous advantages and merits, such as how I do it."
"These merits are better control and output. A semi-equilibrium system means that the excess energy won't go to waste but will enhance oneself from the inside. There are much more, but I want you to find that out on your own." he ends.
Rias nodded, seeing the merits of learning such a thing, but she did have one question. "If this method is so potent, then is it not used more commonly?" she asked.
Issei sighed, "I thought the same when I first learnt this method and even doubted its potency. The only thing I can assume is that it's something that isn't known and is new", he answered.
Rias raised a curious eyebrow, "Does that mean you created the cultivating technique?" she asked.
Issei shrugged, "I guess... that would also mean that you're the second person to learn this method." he replied.
In truth, the system taught Issei to cultivate; the tasks that were presented to him, such as meditation and energy control, allowed him to learn the art of cultivating. This was all during his two-year training.
Rias's eyes sparkled with pride at Issei's words. "I'm honoured," she said sincerely.
Issei nodded, "Well, if you need anything, I'll be over there..." he said as his eyes turned to the section where the city once stood.
Rias's eyes widen as she snaps out of her concentration, "What? You're leaving me?!" she exclaims.
Issei's gaze turns back to Rias while narrowing, "Did you think I was going to hold your hand throughout the training?" he asked in an impassive tone. "Remember, you're on my time; I also have things to do."
Rias's frustration bubbled over as she stood up, her hands clenched into fists. "I understand that, but you can't just throw me into this without proper guidance!" she argued, her voice tinged with desperation.
Issei starts to glare at Rias for her outburst, "All you're doing is meditating; I'm not sure why you're making a fuss over this ", he replied in the same tone.
Rias had the decency to look sheepish; in actuality, she just wanted to spend more time with Issei. "Look, what if something bad happens? As my body explodes because I cultivated wrong?" she asks in an embarrassed tone.
Issei's face contorted with annoyance, "Nothing of the sort will happen; make the most of the time you have here; not only do I have things to do, but I also have to accomplish them by 5 pm." he replied.
Rias's ears perked up, "What's happening at 5 pm?" she asked in a curious tone.
Issei slid his hands in this pocket before replying, "I have to be somewhere at 5", he says, his mind drifting to spending time with Astrid again; since Rossweisse was swamped with her school job, he had to fill for her.
Rias suddenly got suspicious, "He said the same thing last week after his fight with Cao Cao," she thought as she remembered Issei leaving the Underworld suddenly at 5 pm. She then remembered Akeno's teasing of Issei and this Rose girl and realised he would see Rose after training her.
The realisation made Rias scowl, "This two-timing bastard..." she thought in a mixture of anger and jealousy as she stared at Issei.
The change in emotions caused Rias's cultivating to falter, and instantly, a rumble came from her tummy. Rias flushed in embarrassment, his face turning as red as her hair as she looked away.
"Sorry, Issei", Rias apologised. "I haven't eaten since I woke up..." she said meekly.
Issei held an expressionless face before turning around and walking away, "Starve, learn some discipline. I'll give you food when you've earned it. I'll be back in an hour, so just continue cultivating." he said dismissively.
Rias watched Issei walk away, feeling a mix of frustration and resolve. She knew he was strict and demanding, but she couldn't deny the results he achieved. With a deep breath, she closed her eyes and resumed her meditation, focusing on her energy flow.
As she sat there, trying to guide the energy more efficiently, her thoughts drifted back to Issei. Despite his harshness, she admired his strength and dedication. "If I can master this, maybe I'll finally be able to stand beside him as an equal.", she thought.
As Issei left, he thought about what he could train in the free hour. He took on a thoughtful expression, "What exactly can I train? This week, I only focused on my new magic and didn't have time for anything else..." he thought.
Ddraig, aware of Issei's thoughts, decided to add his piece. "Partner, if I may, perhaps you should train your aura", he suggested.
Issei raised his left hand and stared at the glowing red gem on the back of his hand, "My aura?" he asked for clarification.
"Yes, you were just teaching the Gremory how to cultivate; aura is the complete opposite of cultivating since it involves the expenditure of power rather than holding it within," Ddraig explained.
"I've noticed when you use your Aura, you just release the build-up energy from within, and while I know it's effective, it can be better", he continues.
Issei nodded in understanding and acknowledgement, "I see; how would you have me train?" he asked.
Ddraig hummed in thought, "There are different exercises we could do, such as using aura in short bursts of overwhelming pressure rather than releasing it gradually. Also, we could focus all the aura onto one subject." he presented.
Issei claps his hands, "Alright, I got something to work on until I have to meet with Bratty Red again", he says as he glances in the direction of Rias.
X
After an hour, Issei approached Rias after doing his own training. He held a silver platter in his hand since he had visited his castle to get some food for Rias.
As he got closer, he saw energy flow through Rias's body. There was more calmness to it than before, yet she had a long way to go since cultivating takes time to master.
Issei clears his throat, letting him know he is there; instantly, Rias's eyes snap open in shock.
"I didn't even feel his presence or hear his footsteps," she thought.
"It seems like you made good progress", Issei starts. "Yet you still have a long way to go," he continues, placing the silver platter in front of her.
"I'd say, if you practised it for 20 minutes for 20 consecutive days, you'd be at a would enough level," he finishes.
Rias groaned; she didn't want to meditate for 20 minutes daily. "Really? Twenty minutes per day?" she asked.
Issei's jaws clenched lightly at Rias's reluctance, "You waste your time watching multiple anime episodes per day. If I'm not mistaken, a single episode is around 20 minutes. Can you not spare 20 minutes of your leisure time to do something more productive?" he asked sceptically.
Rias bit her lip, knowing Issei was right. She did spend a lot of time on leisure activities, and if she wanted to improve, she needed to make sacrifices. "Fine, I'll do it," she said, her voice tinged with resolve.
Issei gave a curt nod, "Good. Now eat up."
Rias lifted the lid of the silver platter, revealing shrimp fried rice; her eyes lit up at the sight. The aroma alone was enough to make her mouth water. She picked up a pair of chopsticks and began eating, savouring the delicious flavours.
As she took the first bite, she almost orgasmed. "Wow... Issei... this... is... so.. good.." she mutters in a tone filled with ecstasy and bliss. "Did you make this?"
Issei didn't say anything but just nodded in confirmation.
As Rias savoured the shrimp fried rice, she couldn't help but marvel at Issei's talents. "You really are full of surprises, Issei," she said between bites, her voice tinged with admiration.
Suddenly, an idea popped into Rias's head, "Hey, you can change the time in this dimension, right? You said you spent two years here while only a week passed in the real world. Why can't you do that now?" she asked.
Issei glanced through the corner of his eyes, "I don't want to spend more time with you than I need to," he replied.
Rias's heart sank slightly at Issei's blunt response, but she quickly composed herself. She knew he was always straightforward and appreciated his honesty, even if it sometimes stung. "Fine," she said, her tone filled with resignation.
Issei rolls his eyes, "Anyways", he starts as a paper and pen appear in his hand. "here", he says as he hands the items to Rias.
Rias put her fork down and took the paper into her hand, "What's this?" she asked while overlooking the paper.
"It's an NDA", he answered.
Rias blinked in surprise. "An NDA? Why do I need to sign this?" she asked, her curiosity piqued.
Issei's expression remained impassive. "The technique I taught you is something I don't want it spreading without my permission. By signing this, you're agreeing not to share the cultivating method with anyone else," he explained.
Rias nodded slowly, understanding his reasoning. "Alright, I'll sign it," she agreed, taking the pen and quickly signing her name on the dotted line.
Issei took the paper back and made it disappear with a wave of his hand.
"If I may ask, why did you only teach me the cultivation method and not Akeno and Kiba?" Rias asked, curious since Issei hadn't taught this method the previous week.
"It's because, unlike you, they didn't have a problem with their energy control, and I knew that they didn't have enough time to learn this method due to the short time frame till their exams," he answered. "And besides, unlike them, you have a unique ability, Power of Destruction, and I wished to see what one could achieve with the cultivation method."
Rias listened carefully, absorbing Issei's explanation. "I see," she said, nodding thoughtfully. "That makes sense. Thank you for trusting me with this technique."
Issei nodded, "Well, finish your food. We got other things to do," he said.
Rias raised an eyebrow, "What will we be doing next?" she asked.
"There are some techniques which I want you to learn, although I won't teach you the whole thing; rather, I'll lay the foundations for you to learn on your own," Issei answered.
"Techniques?" Rias questioned.
Issei took a moment before replying, "There are three techniques on the top of my head which I wish to see if it applies to Power of Destruction." he clarified.
"I see", Rias responded, taking another bite of the fried rice.
X
After Rias finished her meal, Issei started on the next part of her training.
"Right, now that you've grasped the basics of cultivating, you should have better control over your energy than before." Issei starts. "The first technique I want you to learn is something called 'skin'".
Rias raised an eyebrow, "Skin?" she asked curiously.
Issei nodded, "Yes, it's a technique that I don't employ personally because I don't have something like Power of Destruction. The aim is to release the build-up of cultivated energy through the pores of your skin to create a second layer of skin. If my theory is correct, then you should have a skin that will destroy anything that tries to hit you," he elaborates.
Rias, hearing the explanation, narrows her eyes in confusion. "This sounds a lot like an aura," she voices.
Issei scoffs, "Yes, it does, doesn't it? Aura is what you get when you can't control the energy expulsion from your body. When you see me fight, do you see a glow around my body? Or did the ground beneath me crack? Is the air getting more dense? Or is the weather changing? This is all a mass waste of energy. If I want those phenomena to occur, then it will be because I allowed them to occur, not because of excessive waste of energy," he illustrated.
Rias nodded slowly; she realised that, despite Issei's strength, such phenomena didn't occur as he fought. Now she knew that it was because he didn't allow a single drop of his energy to go to waste.
"So aura is a waste of energy?" she asks.
Issei nodded approvingly, "Yes, there is no merit to using aura aside from intimidation factor. The only exception to this rule is if the aura is specialised, like your brother in his true form", he answered.
Rias's brows furrowed. She hadn't seen Sirzechs's 'Human-Shaped Aura of Destruction' but had heard the stories. Sirzechs converts his entire body inti the Power of Destruction that destroys everything regardless of his will. She was confused about how Issei knew that form and how he understood it.
"How do you know what my brother's true form is?" she asked in curiosity.
Issei took a long pause, "One of my predecessors of the Boost Gear, Mary the first of England", he started before Rias cut him.
"You're telling me Bloody Mary herself was once the host to the Boosted Gear?!" she exclaimed in shock.
Issei sighed but nodded, "Yes, she was known as 'Bloody Mary' for a completely different reason." he said, referring to a once red Scale Mail.
Queen Mary, the first of England and Ireland, was once a user of the Boosted Gear. She was known for her persecution of Protestants in a vain attempt to restore the Roman Catholicism in England. Using the Boosted Gear, she was able to gain much success for her country.
"As I was saying, Bloody Mary was around the time of the Devil Civil War and like many of my predecessors, she was impulsive and arrogant. When she witnessed your brother's true form, she rushed in to fight him, only to be killed by his aura," Issei continued.
Rias nodded; she had expected her brother to win. "So your predecessor was able to show you her memories?" she asked, remembering that one of the former Red Dragon Emperess talked with Issei when he went to Kyoto.
Issei bristled at the question, realising he had to lie. "You could say that" he answered.
Although it was a complete lie, none of the former hosts of the Boosted Gear existed after Dark-sei had killed them all. When Ddraig and Issei visited the place of residents of former hosts within their shared mindscape, all they found was a shelf filled with books.
These books recounted the lives of each host; one of these books was Bloody Mary's. Although the souls of the hosts had perished, their memories had remained.
His musing was broken when Rias spoke up again, "So what did you think of my brother's true form?" she asked, hoping to get Issei's opinion.
Issei hummed a bit, "Well, I saw it through eyes that weren't my own, so I can't give a fair assessment. But based on what I saw, it is a tremendously powerful form. But that form is not only the pinnacle energy waste; Sirzechs must also feel mass fatigue after he depowers. From both the excessive energy expenditure and also the lack of energy present," he replied.
It was an honest opinion Issei had, but we also knew such a form could not be controlled easily, comparing Sirzechs's true form to his own Satanifcation—both forms which are overwhelming and are the pinnacle of excessive energy expenditure.
Rias listened intently, taking in Issei's perspective. She had always admired her brother's power, but hearing about the drawbacks of his true form gave her a new understanding. "I see," she said thoughtfully. "Thank you for sharing that with me."
Issei nodded, "Now, back to your training," he said, redirecting her focus. "To create the 'skin' technique, you need to channel your cultivated energy through your pores, not expelling it wildly like an aura but controlling it to form a protective layer."
As Issei described it to Rias, her thoughts raced over learning how to do it. She listened closely. She nodded slowly, "I understand. So, how do I start?"
Issei gestured for her to stand. "First, focus on cultivating your energy as you did before," he instructed. "But this time, instead of keeping it within, try to guide it towards your skin. Visualise it seeping through your pores and forming a protective layer around you."
Rias took a deep breath and closed her eyes, centring herself. She focused on the energy within her core, feeling its warmth and flow. She guided it outward, slowly imagining it spreading through her body and reaching her skin. She concentrated on maintaining control, ensuring the energy didn't disperse too wildly.
Issei observed her closely, noting the faint shimmer that began to form around her. "Good," he said. "Now, try to keep that energy steady. Make sure it's evenly distributed and doesn't fluctuate."
Rias furrowed her brow in concentration, her breathing steady. She could feel the energy coating her skin, a tingling sensation spreading. It was challenging to maintain the balance, but she persisted, pushing through the initial discomfort.
Issei nodded in approval. "That's it. Keep refining it. The more you practice, the more natural it will become."
Rias opened her eyes, a determined look on her face. "I can feel it," she said, her voice filled with excitement and focus. "It's like a second skin, just as you described."
"Good," Issei replied. "Now, let's test it. I'll throw a weak attack at you. Try to maintain your focus and keep the energy steady." he instructs as he raises his palm towards Rias.
[Ability Used: Energy Manipulation: Energy Generation]
Rias nodded, bracing herself. Issei summoned a small, controlled burst of energy. He aimed it at Rias, watching her closely as it flew towards her.
Rias held her ground, focusing on her cultivated energy. As the attack hit her, she felt a slight resistance but no pain. Due to Rias's innate ability of destruction and erasure, the energy ball that had been launched was destroyed before it could reach Rias.
Issei observed the interaction closely, nodding in approval. "Excellent," he said, noting the success of the technique. "You managed to maintain the skin while neutralising the attack. That's a good start."
Rias looked at her hands, feeling a sense of accomplishment. "I did it," she said, a smile spreading across her face.
"Indeed, but don't get complacent," Issei cautioned. "This is just the beginning. You'll need to practice this regularly to make it second nature. The true challenge will come when you have to maintain this skin under continuous and stronger attacks."
Rias nodded, her determination renewed. "I understand. I'll keep working on it."
Issei gave a slight nod of approval. "Good. Now, let's move on to the next technique. This time, I want you to concentrate your cultivated energy into your eyes. The aim is to use Power of Destruction from your eyes; by doing this, you should theoretically destroy things just by glancing at it," he presents.
Rias's eyes widened at Issei's words; the idea of using the Power of Destruction from her eyes sounded both thrilling and daunting. "Concentrate it into my eyes? That sounds... intense," she admitted.
Issei nodded, his expression serious. "It is, but it's also incredibly powerful if you can master it. The key is to focus and direct your energy with precision. Start by cultivating your energy as before, but this time, channel it towards your eyes." he reassured.
Rias took a deep breath; she closed her eyes, centring herself again. She visualised the energy flowing from her core, through her body, and into her eyes. It was a different sensation, more focused and intense.
Issei watched her closely, noting the faint glow emanating from her eyes. "Good," he said. "Now, try to maintain that focus and direct the energy outward. Imagine it forming a concentrated beam of destruction."
Rias furrowed her brow, concentrating harder. She could feel the energy pooling in her eyes, a powerful force waiting to be unleashed. She opened her eyes slightly, focusing on a small rock nearby. She tried to direct the energy towards it, willing it to be destroyed. A faint red glow emanated from her eyes, and the rock began to crack and crumble. It wasn't as instantaneous as she had hoped, but it was a start.
"I did it," Rias said with a hint of amazement.
Issei nodded, satisfied with her progress. "Good. It's a solid first attempt. The more you practice, the more control you'll have over it." he stated.
Rias nodded, feeling a surge of resolve. "I'll keep practising. I want to master this," she replied.
Issei gave her a rare smile of approval, "So what do you plan on naming this new technique?" he asked.
Rias blinked in surprise, "Are you letting me name it myself?" she questioned.
Issei shrugged, "Well, it's your technique; it's only your right..." he elaborated.
Rias's eyes sparkle in surprise and joy, "Well... how about... eyes of destruction?" she suggested.
Issei thought momentarily before nodding, "Yes, that is quite fitting considering its potential. Anyways, these techniques, like every other technique, will grow as you practise. But if you cultivate alongside their individual training, these techniques will also grow passively," he explained.
Rias absorbed Issei's words, feeling excitement. "I'll make sure to practice both the cultivation and the techniques regularly," she said.
Issei nodded approvingly. "Good. Now, let's move on to the final technique I want to introduce to you today." He paused for a moment, ensuring he had her full attention. "This technique involves manipulating the Power of Destruction into a concentrated form, creating a weapon of pure destructive energy."
Rias's eyes widened slightly, intrigued by the concept. "A weapon of pure destructive energy? How would I go about doing that?"
Issei explained, "It's similar to how you channel the energy for 'skin' and 'Eyes of Destruction,' but instead of dispersing it through your skin or eyes, you'll condense it into a tangible form, like a blade or spear. The technique is called 'flow'"
Rias nodded, understanding the challenge. "I see. So, I must focus on condensing the energy and giving it a solid form."
"Indeed," Issei affirmed. "Start by cultivating your energy as usual. Once you have a steady flow, visualise it condensing into the shape of a weapon. As for the weapon's shape, you aren't a close-ranged fighter, so something long-ranged will be more suitable." he says as he opens a portal and puts his hands through.
He then pulled his hand out and revealed a white bow, which looked quite simple. But this didn't matter to Rias, thinking she might get a weapon from Issei as Xenovia did.
"Is this a weapon from me?" Rias asked with barely concealed excitement.
Issei shook his head, "Not exactly" he answered. "It's a cultivation tool. It allows someone to flow their energy into the tool's shape so the user can learn how to use 'flow' to shape their desired weapons. If the user continues to use this tool as training, eventually, the tool will break, indicating the user no longer needs it to create a flow weapon. Think of it as a stencil," he explained.
Rias's excitement was evident as she took the bow from Issei. She could feel its weight and the subtle energy it emanated, sensing its purpose as a training tool. "I understand," she said, nodding. "I'll use this to practice forming the 'flow' weapon."
Issei nodded in approval, "Good. Start by channelling your cultivated energy into the bow. Visualise the energy condensing into the shape of an arrow. The more you practice, the more control you'll gain over shaping and maintaining the weapon."
Rias closed her eyes, focusing on her energy flow once more. She could feel the warmth of her cultivated energy guiding it towards the bow. As she concentrated, she visualised the energy forming an arrow, seeing it in her mind's eye.
Issei observed her closely, noting the faint glow that began to surround the bow. "That's it," he encouraged. "Keep your focus steady and let the energy take shape." he continues as he points his palm towards the rest of the wasteland.
Instantly, an entire city was formed in the distance. This was meant to be Rias's outlet for the arrow she was producing. Rias opened her eyes, and a small, glowing arrow formed on the bowstring. It wasn't perfect, but it was a start. She aimed at a target and released the arrow, watching it fly through the air at blinding speeds and strike the newly built city.
As the arrow hit the building, a massive explosion occurred, shaking the ground the two stood on. The explosive drew in the surrounding buildings like a black hole before exploding once again. As the dust settled, the entire city was erased, and a large crater appeared in place of the city.
Issei watched the destruction with a satisfied expression, "So, what are you going to call that technique?" he asked., turning to Rias.
He saw her jaw had dropped in shock, never expecting to have such destructive power from a simple technique. It even exceeded her earlier display before she learnt the cultivation technique.
Rias took a moment to compose herself, still stunned by the sheer power of the technique she had just unleashed. "I... I think I'll call it 'Arrow of Destruction,'" she said, still somewhat breathless from the experience.
Issei cringed, his head swaying side to side. He was clearly not impressed with the cliche name. "'Arrow of Destruction'? Sounds to cliche. How about... Crimson Arrow?" he suggested, referring to the crimson-red colour of the arrow when it formed.
Rias chuckled, recognising Issei's point. "You're right; 'Crimson Arrow' does sound better," she agreed.
Issei then clapped his hands, "Alright, now that we got that sorted, time to put all these to practice", he said as he teleported himself and Rias to another island.
Rias took a moment to gain her balance from the sudden teleportation in the form of clutching at Issei's arm. Feeling the contours of his muscles caused her to blush a bit.
Issei looked at Rias, annoyed, already knowing what she was thinking. "Get your head out of the gutter", he commanded, taking his arm away from her grasp.
Rias looked embarrassed, "Sorry... Issei", she apologised shyly.
She then looked forward and saw the new island; it was fairly large, and at the centre was a portal. The portal was purple, seemed to crackle with otherworldy energy, and emitted a low hum.
"What's this place for, Issei?" she asked, examining the area.
Issei stepped towards the portal before replying, "This is a dungeon area. Usually, there'd be more dungeons, but I guess there only seems to be one today. These portals can be entered to fight monsters and whatnot", he answered.
He then points to the current portal, "There are different colours of the portal, such as blue and purple. The blue ones allow you to enter, and the purple one means a Dungeon Break", he continues.
Rias raised an eyebrow, realising the portal before meant it was a Dungeon Break. "Dungeon Break?" she asked for an explanation.
Issei then looked at Rias, "As I said, you can enter these dungeons to fight monsters. But sometimes, the monsters from within the portal use the portal to enter this place; that is what you call a Dungeon Break." he answered.
Before Rias could say anything, the portal started to screech. Instantly, a horde of mutated insect-like entities emerged; this was the dungeon break.
Issei then signalled his head towards the horde, "Go on, put your new techniques to practice..." he told Rias.
Rias took a deep breath, feeling the weight of the moment. This was her chance to put everything she had learned into action.
She nodded at Issei, "Alright," she said, stepping forward and summoning her energy.
Issei had watched Rias from hovering in the air; he noticed that her energy expenditure had significantly been reduced, thanks to the cultivation techniques. The other techniques she learnt were helping alongside.
Something that he took notice of about Rias is that she had no space awareness. Sometimes, she got hit from within a blind spot but was only protected by the skin technique. This is something he was going to work on with her now that she has a good baseline.
After a while, Rias began to get overwhelmed by the sheer number of insects, so Issei decided to help. He descended from the skies and provided air support to Rias with energy blasts, obliterating the hordes of insects.
X
After an hour, the two were on a bench in a forest area. Issei was sorting out the loot he got from clearing the Dungeon Break. This consisted of vials of venom, silk and a mutated chitin. Rias watched Issei sort through the items. She asked him why he was collecting them, and he told her it was good crafting material.
This made her feel a bit bad; she had been carelessly obliterating the hordes of insects left, right and centre. Not being considerate that Issei may have wanted to harvest the goods.
"Sorry, Issei, I should've held back a bit," Rias apologises solemnly.
Issei continued to sort out the items, "Don't worry, Rias. If I wanted to harvest as I wanted. Then I wouldn't have asked you to do the Dungeon Break", he reassured in his usual tone.
Rias felt slightly relieved at Issei's words, though she still wanted to be more mindful in the future. "I'll try to be more careful next time," she promised.
Issei nodded dismissively, "Your progress is good, but there is still more to the cultivation technique than what you have learnt, from being able to draw in the energy from your surroundings into your body, to enhancing your body's attributes. Maybe one day I'll write a book on the ins and outs, then exclusively give them to my descendants because I'm that stingy," he says nonchalantly.
Rias chuckled softly at Issei's comment, appreciating his usual dry humour. "You plan on gatekeeping the cultivation technique?" she asked.
"Mhm", Issei mumbled. "There's a step above cultivation, which is called Thrivation. It is based on growth, but it's all theoretical, and I'm still figuring it out. Hopefully, it's not a waste of time."
"I'm sure it won't be, Issei" Rias spoke reassuringly.
Issei put another vial of venom away, picking up another, "Speaking of which, do you want to know what the biggest waste of time I ever had?" he offered.
Rias tensed up, thinking he might say something mean again. "What is it?" she requested, a bit on guard.
Issei had a faraway look in his eyes, "During my 2-year training, I learnt martial arts. But I hardly ever have the time to use them since the supernatural world is mainly castors instead of hand-to-hand fighters.", he answered.
Rias looked curious, "Martial Arts? Which one did you learn?" she asked, wondering which of the many worlds Issei learnt Martial arts.
"All of them", Issei answered bluntly.
Rias's eyes widen, "All of them?!" she repeated.
Issei nodded, "Yes, all of them. Learning new things is very easy for me. But obviously, I don't use all the techniques. Instead, I picked and chose techniques that I liked and found useful. From there, my true Martial Art was created. It's called 'Absolute Lethality'," he explained.
"Absolute Lethality?" Rias muttered in wonder.
"Yeah, a Martial Art based on how lethal my attacks are. This means I dispose of my opponent in the most effective and efficient way possible... which usually means my opponents either die or get maimed." Issei explained.
A shiver ran down Rias's spine, remembering that Issei, using his body to fight rather than weapons, tends not to hold back and completely dominate them. "I see", she replied.
Issei decided to give Rias an example, "For instance, there is this one technique which I use." he says, his hand outstretched and heading for Rias's bust.
Rias freezes up in response, "Issei... what are you doing?" she asked nervously.
"This technique is something which I can't use on women due to their breasts, so I can only use it on men. I start by thrusting my hand forward and grabbing onto their chest; my fingers dig through their skin and flesh, grabbing onto their ribcage. And finally, I use my immense grip strength to break their ribcage," Issei explains, still staring at Rias's chest.
Rias's eyes widened in horror as she listened to Issei's explanation. She could almost feel the imagined pain as he described the technique in graphic detail. "That sounds... brutal," she said, her voice a mixture of awe and discomfort, trying to compose herself despite the situation's awkwardness.
Issei then withdraws his hand from Rias's chest, "There are other aspects to my Martial Arts such as the 'Invisible Strikes'. These strikes are specialised; as I wait for my opponent to attack, I then counter by hitting them in their blind spot with immense speed. To my opponent, it looks like they've been hit with an invisible attack." he added.
"Another aspect is my technique to steal someone else's technique", he continued.
Rias raised an eyebrow, "Steal someone else's technique?" she asked with interest.
Issei nodded, "Yeah, stealing someone else's technique. It works by me seeing my opponent using a technique once, and I then replicate the technique. However, I changed the rhythm and pacing of the technique so that my version is superior to theirs. When they see the improved technique, they try and do the same. However, they fail, and this causes a sense of doubt, uncertainty, and insecurity within them, forcing them to stick to what they know. So every time they try and perform the stolen technique, those senses make them either fail the technique or not be able to bring out its full potential ever again," he explained.
Rias listened in awe, "That's incredible," Rias said, genuinely impressed.
Issei shrugged, "There are other aspects I'm working on, like the infinite technique and an improved invisible strike, which can be done without it being in my opponent's blind spot. But I have hit a brick wall regarding my Martial Arts; as I said, the Supernatural World doesn't use hand-to-hand combat much, and those who do aren't on my level. So there is no way for me to improve; perhaps I should become evil and allow the entire Supernatural World to jump me so I further improve my Martial Arts," he says uncaringly.
Rias chuckled nervously, unsure if Issei was serious or joking. "Let's not go that far," she said, trying to lighten the mood.
Issei sighed, "I'm serious; when I fought Ares yesterday, I was hoping that the Greek God of War would allow me to reach new levels, but unfortunately, I was left disappointed", he replied.
Rias perked up, "I totally forgot; how did the meeting with the Greeks go yesterday?" she asked in remembrance.
Despite Issei leaving the meeting early, the other leaders stayed behind to talk with the Greek Pantheon. When the meeting finally ended, everyone in Kuoh was dead asleep, so Rias didn't know how it went; the fact that Issei was in front of her and casually meant that it either went well or satisfactorily.
"Well, my actions against Hades were cleared up, and they apologised for his crimes on his behalf. We shared information about this Qlippoth Faction and the stolen half of Ophis. In exchange, they told us some of their own had gone rogue, such as two Primordial Gods, the dimension Tartarus has gone missing, and there is a prophecy about some child," Issei explained, giving her the rundown.
Rias listened intently, her brow furrowing in concern as Issei recounted the events. "That sounds... intense," she commented. "Two Primordial Gods going rogue, a missing dimension, and a prophecy about a child? It seems like there's a lot going on. Do you have any idea who the rogue gods might be or what their intentions are?"
Issei nodded, "Yes, Erebus, the Primordial God of the Darkness and Nyx, the Primordial God of the Night. As for their intentions, no one is sure. All we know is that they may have been in league with Hades", he answered.
Issei then glances over to Rias, "I shouldn't mention The Furies... she might start getting more concerned than she needs to be", he considered. From what he knew of The Furies, they were vicious and ruthless, a threat that only the likes of himself could handle.
Rias looked away in thought, "I guess it's good that I'm getting training from you then. Akeno has the Grimoire you gave her, Kiba had his eyes open from when you possessed him, Koneko is getting trained by Kuroka, Rossweisse is training Asia, you trained Rossweisse, you bullied Xenovia into utilising her Ex-Durandal even more, and Gasper has awakened something from within himself." she stated.
"It was about time for me to start my own training. Despite training alone, I felt quite unproductive because I didn't have someone training me personally. Thank you, Issei, for training me today; I learnt a lot." she says appreciatively.
Issei stopped his sorting and looked at Rias through the corner of his eyes, "You're welcome", he replied. "Akeno, Kiba, Asia, Koneko and Gasper... compared to them, we've lived quite sheltered lives, haven't we?"
Rias was a bit surprised at the change of conversation, but she had to agree. "Yeah, we have", she replied.
"I don't know if I should be telling you this, but..." Issei started. "Last week, when I sent you guys to my dimension while I fought Shalba and saved Ophis, I met with Great Red.
Rias nodded, remembering the event. "Yes, you said that you left Ophis with him," she replied. "What is it that you want to tell me?" she asked, a bit hesitant.
"Speaking of which, I should check on Great Red and Ophis... hopefully, they haven't killed each other..." Issei thought before answering Rias.
"Well, Great Red, being as powerful as he is, told me that this reality we know has multiple timelines", Issei spoke, causing Rias's eyes to widen.
"Multiple timelines?" Rias murmured.
"Indeed", Issei replied. "I won't tell her about the original timeline in which Devils didn't exist until my birth, which caused reality to shift since even I didn't know the implications," he thought.
"In one of those many timelines, I never changed. I continued being an immature brat who only thought about boobs," he continued.
Rias's eyes soften, imagining a timeline where her actions didn't cause Issei to change this drastically and resent her. However, Issei's following words would shake her.
"But because of this, I had no way to counter Samael's curse as I did in this timeline with those nanites I injected myself with. So when I fought Shalba to save Ophis, he hit me with an arrow dipped in Samael's blood, and I died," he explained, his tone cold.
Rias felt a chill run down her spine at Issei's revelation. The thought of losing him in another timeline, even one that wasn't her own, was unsettling. She couldn't imagine a world without Issei, especially after everything they had been through together.
Issei took Rias's silence as she contemplated, seeing her eyes becoming watery and looking side to side. "Regardless of which version of me you prefer, one thing you can't deny of my current self is more competent than my former self. Tell me, you'd rather live in a world where I'm more serious or in a world where I'm dead?" he asked, already knowing the answer.
Rias looked down, her voice barely above a whisper. "You know the answer to that, Issei," she said, her tone filled with sadness. "I'd rather have you serious and alive than the alternative. The thought of losing you, even in another timeline, is terrifying. I can only imagine what my alternate self went through..." she finished, looking at the thighs.
Issei then glanced to the side and saw a red ghostly hand rising from the ground, holding a binder. This was one of Issei's legions; he had tasked them to write up a binder filled with potential techniques for Rias to learn. He took the binder from the ghostly hand and put it in front of the solemn Rias.
"Enough of that sad shit", Issei says bluntly. "Here, take this; it's filled with techniques and tips on utilising the cultivation technique even more."
Rias opened the binder, seeing a lot of bold stick figures that were animated; this awed her. The moving stick figures demonstrated various techniques on how to use cultivation better.
Before Rias could respond, Issei spoke. "Just remember the NDA I made you sign. Don't show that to anyone or lose it," he said sternly.
Rias continued to look at the moving images, still in awe. "Thank you, Issei. But how were you able to do something like this?" she asks, pointing at the moving images on the paper.
Issei smiled awkwardly, "It's all Rossweisse's fault; she made me read Harry Potter and whatnot..." he thought, remembering that Rossweisse had convinced Issei to read various fantasy books such as Harry Potter and Lord of the Rings. But it was worth the read to Issei since he was entertained, and Rossweisse was eager to quiz him.
"Well, I'm always working on new types of technology and whatnot. And it just so happens that I found a way to make paper that had moving images." Issei answered.
Rias looked up, "How does that work?" she asked curiously.
Issei held his hand up, and various types of pencils and pens appeared instantly. "These tools are made for such uses. You draw the first frame, scribble over it with another tool, and then repeat. After that's all done, you get moving images," he answered.
Rias's eyes sparkled, "Do you plan on selling those? It will be a big hit", she suggested.
Issei scoffs, making the tools in his hands disappear. "Not sure..." he replied. "Anyways, there is one more technique I want to show you. It's in the binder, and I suggest you learn this technique before you move to the others," he said, standing up.
He walked over to the clearing so Rias could see the technique. "I've taught you how to cultivate and control the energy through your body. Then, I taught you how to release it from your body efficiently. But now I'm going to show you how to exert that energy into the environment to amplify your abilities." he states.
Rias nodded attentively, making sure to see what Issei was doing. Suddenly, around Issei, a circle forms on the ground. The circle had a blood-red glow and red and black energy arcing off the rim.
"This is called Field Projection; by using this technique, you can amplify your abilities, whether offensively or defensively," Issei explained. The circle suddenly got bigger, now encompassing Rias. She felt a wave of dread while within Issei's field projection; she clutched at her body in pain, although it wasn't enough to cause too much distress.
"You watched Bakugan, right? Do you remember when they opened a Gate Card?" Issei asked.
Rias nodded, still tense. "Yeah, it allowed the Primary Bakugan to gain a home-field advantage, whilst any other Bakugan would gain a disadvantage..." she muttered.
Issei smirks, closing his field projection. "This technique is basically that", he continued.
Rias rose to her feet, her breathing gradually coming to rest. "I see, and I assume you think that my Power of Destruction would have a unique effect?" she asked for clarification.
Issei nodded approvingly, "Yeah, it should yield similar results to the other techniques and then some", he answered.