Chapter 2 – Dungeon Maker

Cain could not believe what he saw. The Bishop nodded, confirming that this was indeed his fate. He couldn't believe that he was supposed to die like this.

"If you become the King, then I will erase your existence in your world." The Bishop said. "But, you can also refuse the offer if you want and that will be your future. Now, let's see the future if you accept this proposal."

He snapped his fingers and the scene in the window changed. A man was sitting on the throne, surrounded by golds and jewels. Behind him stood a group of monsters, all looking like humans with different kinds of weapons.

The group was watching a red-haired woman and what seemed to be her followers running across a cave, defeating goblins and wolves. It seemed like they were clearing a dungeon. A boy with brown hair and red gloves was punching the goblin while leering at the women in the group lecherously.

Cain recognized them.

"Rias and her peerage?"

Soon, the screen changed again to show another scene. Each one had people he recognized, someone who shouldn't have existed in reality.

After a while, the darkness returned and the Bishop said, "Now, choose."

"Can you repeat it?"

"If you choose to refuse, the fate shown in the beginning will happen. However, you will have a chance to survive if you accept the offer to be the first King. We will give you powers beyond human's capabilities and a safe passage out of your world, as well as an ability to travel through different dimensions and worlds."

Travel through dimensions and worlds. Which meant it didn't just end in reality but he could travel to anime and manga he knew, like Highschool DxD and others. He might have a chance to meet characters he liked or hated and get to know them personally.

"Take your time."

"No, I have decided." Cain quickly stood up, and declared proudly, "I will be the King."

"Excellent. I shall give you a ring. Wear this and it will grant you access to the System. Once you have been transported to the destination, your role as the King shall commence. And if there is duty, then there is reward. Do your best."

The Bishop snapped his fingers once again, and Cain found himself wearing a silver ring on his right index finger. As soon as the Bishop touched it, a red gem glowed brightly and a notification appeared.

Ding*

A deep and robotic male voice resounded in Cain's mind.

[You are now in the King's Tutorial!]

[You have 2 hours to finish the King's Trial. Your performance shall decide the rewards that you shall receive. There is a chance that you may die, please be careful.]

'King's trial...?' Cain thought. He was still trying to take everything in and figure out what the hell just happened to him when another message appeared.

King's Trial 1:

Create a 2 floors Dungeon.

When he realized it, Cain found himself in a strange room. It looked like an underground cavern, but there was no dirt or rock to be seen.

A window that was often seen in video games floated in front of him and he saw the objective of the first trial. The room had nothing in it, only the floor was covered in stone tiles.

'Is it a game?' He asked himself. Then, a screen popped up with the title: King's Tutorial.

A robotic voice was speaking from the ring on his finger.

[Dungeon Maker System, it's a system where the King is in control of everything in his territory. Place traps, summon monsters, and gather coins to upgrade and buy something from the dungeon store. You can get coins from the challengers that enter the dungeon.]

[You have been given 500 Coins for early setup.]

'System?' He muttered. He had played video games enough to know that it was a game-like thing, or maybe a real-life RPG.

In a fantasy or medieval world, a dungeon is a type of monster nest where adventurers would enter to train and earn money. But, in reality, it's just an empty room with no monsters.

What's the point of creating such a thing?

"I am the one filling the dungeon?"

The windows in front of him showed a list of monsters and traps he could place. Each cost coins, which he currently had around 500. Based on the price he saw, he might be able to create a newbie dungeon with some traps and weak monsters.

"How do I get coins, though? It said I can get it from the challengers."

Just as he asked that, the voice replied from the ring, answering him as if the ring understood him and his confusion.

[The Dungeon will convert the challengers' emotion into energy and generate Coins. Every emotion generates a different amount of energy. Negative emotion generates the most energy, and fear generates the highest.]

Listening to the description, Cain nodded. He understood what it was saying. But...

"The worlds I am connected with will be those anime worlds. And there are fearsome people in those worlds. Making them fear my newbie dungeon is... bad idea. I don't want to get killed by a siscon Crimson Satan or other overpowered anime characters."

To move forward, he had to create dungeons and get coins. These coins were versatile. In fact, he could see various things he wanted to buy in the dungeon store. It was basically an app store. There were a lot of features he wanted, but didn't have the money for.

'I have 2 hours... I should finish this as soon as possible.'

He then looked around the empty space he was standing in and decided to create a basic 2-floored dungeon with the help of the Dungeon Maker system.

'First, the setting... Let's make it a fun dungeon where people can get revived. That way, I can farm their joy and adrenaline and don't risk angering their backers. I don't want to die.'

With that, he began to work on the dungeon with his limited coins. He decided that he would make a fun adventure dungeon that everyone could enjoy.

He placed traps and monsters at strategic places so that they would not be too hard for newcomers to beat but also challenging enough for experienced players to enjoy themselves.

When the countdown of his mission reached the last 1 minute, Cain managed to finish the dungeon he envisioned with 500 Coins.

"Phew, I managed to finish it on time..." Cain sighed in relief and smiled. He looked at his masterpiece and felt proud of himself for doing such a good job in such a short amount of time.

Suddenly, a window appeared before him. It read:

[The King's trial is over. Connecting the dungeon's entrance to another world. Please give it a name.]

"A name, huh?" Cain stroked his chin as he leaned back to his throne.

After a moment, he said, "Let's name it the Fun Fun Dungeon!"

And just like that, he decided on the name.

[Name decided. Connection in progress.]

[Connected! Fun Fun Dungeon! is connected to Highschool DxD World.]

"Oh!"

Chapter 3 – Fun Fun Dungeon!

Kuoh Academy.

The destruction caused by an attack from a fallen angel affiliated with Grigori, Kokabiel, had disappeared as if nothing happened. This was done by the magic of a devil who was sent to eliminate the intruder.

Kokabiel had attacked Kuoh town, where the main base of the Gremory family, one of the 72 pillars of the underworld, was located. He wanted to use the lives of civilians to force the Gremory's heir and other devils to submit.

The attack ended up as a three-way fight between the fallen angels, devils, and the church.

And now, everything was over and returned to normal.

A red-haired girl sat behind a desk with paperwork piled up. She was sighing tiredly, and it looked like she had been working since morning. Her expression was that of someone who had worked for a very long time without any rest. Her blue eyes seemed weary.

She wore a uniform that all girls from Kuoh academy must wear, a black blazer, with a white blouse underneath, and a corset-like top. A black tie was hanging from her collar. Her short red skirt showed off her shapely thighs and long legs, along with her white knee-high socks and black school shoes.

She is Rias Gremory, a third-year student and a king among devils.

"Phew, it's finally done. I need a break."

As soon as she finished her work, Rias leaned back and let out a relieved sigh. Her friend as well as the Queen in her peerage, Akeno, brought tea and cake for her. The black-haired beauty in her school uniform smiled and handed her the tea and cake. Rias gratefully took them, then asked about the status of the school.

"It's going smoothly, President," said Akeno as she took a seat next to her.

"I see... Thank you for your hard work."

"No problem. Oh, and there is one more thing. We found a strange thing after fixing the backyard of our Occult Research Club. Maybe you should see this."

"A strange thing?" asked Rias curiously as she put down her cup and saucer on the desk. Akeno nodded and led Rias to the window.

From the window of the second floor of the old school building, they could see the backyard of the building. And in the middle of the backyard, a cave-like structure stood tall. The entrance was large and wide enough for three people to stand side by side, with a wooden board with the words, "Fun Fun Dungeon!"

"What... Is this thing?" asked Rias, confused by what she saw. She had never seen anything like it before in her life. Akeno shrugged.

"We don't know. But I don't think we should check it out, President. It might be a trap that Kokabiel or the fallen angels left."

"It's more dangerous if left unchecked." Rias rose up and went downstairs with Akeno. Then, the two of them stepped outside the old school building, approaching the cave.

Rias cautiously looked at the cave with crossed arms, and then turned around to face Akeno.

"Call everyone to gather. We will check together in case we need to fight. Issei-kun and Kiba-kun would be a great help."

Akeno nodded and took out her phone. She called everyone and soon they arrived. A brown-haired boy, a blonde boy, and a white-haired girl.

"I'm here!" Issei Hyoudou, a perverted second year high schooler said. His eyes were glued to Rias's chest. "Wow, as expected, your boobs are really huge, President."

"Issei-kun, please pay attention." Yuuto Kiba, the blonde pretty-boy, sighed. He then turned his gaze towards Rias and smiled brightly. "President, what can I help with?"

"You too. Pay attention." Koneko, a white-haired petite first year, sighed.

"I'm sorry..." Issei scratched the back of his head while laughing nervously.

"It's fine. Anyway, I called everyone because we found something strange." Rias pointed to the cave and explained, "It suddenly appeared here. We have yet to investigate but I plan to enter. To be safe, I plan to have everyone with me."

"I will be more than glad to go." Akeno said.

"Of course! Let me prove to my master how reliable her pawn is." Issei grinned and flexed his arm. Kiba and Koneko also agreed.

"I don't think it's a fallen angel trap, so we don't need to worry about fighting. But we still have to be careful." Rias smiled. Then, she looked serious and asked them to follow her as they walked inside the cave. "Let's go."

The interior of the cave was pitch dark. The group was walking in complete darkness. After a few minutes, they came upon a door.

A sign above the door read, 'Fun Fun Dungeon, 1st floor. Difficulty: G'.

"What is this? Is it some kind of a game?" asked Akeno, confused.

"It's like a dungeon game!" Issei chirped happily. "I'm getting excited. Will there be a female monster? Hehehe, it will be great if they have big boobs!"

"Ara, Issei. To think you would say that in front of me." Rias smiled. She put her hand on his shoulder and said, "It makes me sad, you know."

"Hehehe, of course yours are the best, President!"

"I'm glad." She smiled teasingly, "Now let's go."

As the group continued walking through the cave, the path ahead began to widen. A clearing was waiting for them. And in that clearing, a green-skinned creature appeared. It was holding a wooden club.

It had an ugly face and looked angry, its eyes were bloodshot red and drooling. Five heads turned to them as it roared, "Groooaaa!"

"A goblin!" Issei shouted, he looked scared.

What was a goblin?

In a RPG game, a goblin was usually a weak monster, but in fantasy and medieval era, it was a fearsome monster that appeared in stories and tales.

They were described as small, greenish humanoid creatures with sharp fangs, pointed ears, and red eyes that would eat anything they could get their hands on. In reality, the goblins that lived in forests or caves would hunt and kill humans who wandered too close to them, often stealing children and livestock.

In short, they were dangerous even though they were weaker than devils. That said, these were only stories that humans came up with.

The goblins that appeared before the group were around the height of a human teenager. Their skin was a dark shade of green and their faces were covered with scars from fighting and killing.

Their eyes were large and bulging out of their sockets. They wore tattered clothes made from animal fur or hide.

Cain watched as Rias' group prepared for battle. The goblins raised their clubs high into the air, growling as they charged forward.

Chapter 4 – The Devils Attacked!

The group immediately formed up and attacked.

Koneko, Kiba, and Issei became vanguard while Akeno prepared spells. Rias was at the very back, observing the battle from afar. She wasn't going to participate unless absolutely necessary, but if something went wrong, then she could easily step in.

"Koneko! Be careful!" Kiba said, swinging his blade. Koneko was a close-range combat specialist and would always rush forward first. Her small size gave her speed advantage over her opponents, but her small stature didn't mean that she was weak.

"Hmph!" The Rook shouted as she dashed towards the nearest enemy and kicked it away. She didn't even break a sweat as she did it again to the second goblin.

"Oh! Koneko-chan, you're so good!" Issei cheered for the petite girl.

Lightning fell as Akeno finished her spell, making the goblin panic.

Kiba followed after her. With his light movement, he dodged the incoming club attacks. He thrust his sword at the nearest goblin, then swung it to the left, right, and back.

A second later, two goblins fell on the ground with gaping wounds in their stomachs. Issei had also defeated a few of the monsters himself, although he wasn't as efficient as Koneko.

"We win!"

Still, the joy contained in his voice was infectious and spread through the rest of the group, causing them to laugh and cheer.

However, Rias' serious voice stopped everyone from getting carried away. "No, not yet."

She looked at the narrow path hidden behind a big rock in front of them, and pointed at it, "There's a path over there. We need to investigate this place. How could there be a goblin in here, and what this place actually is, we still don't know."

The rest nodded and they proceeded through the narrow path.

After walking for ten minutes, they found a large clearing with four doors on each wall. One had a signboard saying, '1st Floor Boss Room'. Another sign read 'Stairway to 2nd Floor'.

A third sign said, 'Treasure Chest'. The last one said 'Trapdoor'.

"There are four doors." Rias muttered.

"My, my... What are these doors?" Akeno asked, her voice was laced with curiosity. She seemed interested in this new discovery. Koneko, who stood beside her, looked up and said nothing.

"I don't think it is safe here..." Issei said. "We should leave."

"No." Rias shook her head. Her eyes narrowed slightly as she thought about what could happen if they didn't check all of the rooms thoroughly.

There might be danger lurking inside that had to be destroyed immediately, and they didn't know anything about the place so they had to investigate.

"This place might contain a dangerous being or a trap. We need to clear this place and destroy the source of danger, then we can leave."

"But..."

"We're doing this. First, let's reach the boss room."

They all agreed. With that decided, they headed to the boss room.

It was a spacious hall that had no furniture or decorations, only a single goblin stood in the middle. This goblin was two times bigger than normal goblins.

It looked more menacing than the ones outside. The creature growled and roared loudly, "Gruaaah!"

Everyone was focused on the monster, except for Kiba who realized something.

"The door disappeared!" He exclaimed.

"Huh? You're right!" Issei yelled, he ran towards the wall but found nothing. No matter where he searched, there was no sign of a door. "Oh crap! What should we do? We're trapped here!"

"Calm down, Ise-kun. We can't afford to panic." Rias calmly spoke as she observed the area. "Let's defeat it and then we'll figure out what to do. Possibly the exit will return."

"I don't like this. It feels like we're being toyed with." Kiba muttered as he drew out his sword. "It's too convenient. And if we defeat it, we'll find the way out."

"We don't have any choice, so we can only move forward. Let's go!" Rias said and the battle started.

"Oh, they are doing great." Cain, watching the scene from a window in front of him, grinned.

This was a part of the system that he had created during his preparation period.

After he created the dungeon, Cain could observe what happened in the dungeon, check the map and status of his dungeon. The window showed him how Rias' group fought against the Hobgoblin.

Just like its name, Fun Fun Dungeon!, this dungeon was made to imitate RPG games and anime. The enemies were weak monsters, created to be a tutorial and a way to experiment his Coin farm.

The concept was simple: A fun dungeon where adventurers could have a safe adventure without risking their lives.

"System, explain to me about the Dungeon Maker System."

Ding*

Dungeon Maker System: It's a system that helps the King with dungeon management and administration. This system will assist in the growth of the dungeon and help with its development.

The Dungeon Maker System has many features. He could freely make any dungeon he wanted as long as he had enough Coins, the system would automatically do all the work for him.

And now, the cast of Highschool DxD was fighting the first boss he set in a 'Choose one of the four doors' trap he set for fun. Of course, they wouldn't get hurt and die.

After all, there was no way a Hobgoblin could defeat a group of Devils, with one of them being a high-rank one.

"Rrrruuuoooo!" The Hobgoblin roared, raising its club. Kiba ran to it, slashing his sword at its leg.

The creature stumbled backward as blood splattered across the ground, but it managed to stay standing.

Issei rushed to the monster, his fists clenched tightly.

"Boost!"

He swung his fist, punching the monster's face, forcing it to step backwards.

At perfect timing, a white-haired girl jumped and punched it in the stomach. It caused it to groan and cough.

Akeno and Rias were on standby. Rias was ready to help if needed.

"Grooooaaaaa!" The Hobgoblin roared, lifting its arm and smashing the ground.

Issei, Kiba, and Koneko were sent flying backwards. The Hobgoblin stood tall again, brandishing its club and roaring.

"Let me finish this!" Rias stepped forward, and summoned her demonic powers.

Red lights appeared around her body, forming a magic circle. Then, a dozen red balls shot out, piercing through the air towards the hobgoblin.

The beast was unable to dodge and it roared loudly before falling to its knees.

Rias sighed. "It's over."

"Yay! We win again!" Issei shouted.

Chapter 5 – First Reward

"I see..."

Cain nodded in understanding as Rias and her group celebrated their victory. It was just as he thought; it seemed like the enemies in his dungeons would never win against the challengers for now, so the only way for him to get more Coins was through the 'emotional reward system'.

As long as people enjoyed their adventures in the Fun Fun Dungeon, the dungeon would absorb their emotions and turn it into coins. It didn't matter how many times they lost or got injured.

[Challengers have finished the dungeon.]

A system notification popped up in front of him.

"Choosing the first boss room means they want to end the dungeon on the first floor, though they don't know about that." He muttered. It was the end of the line. The system then displayed a screen, showing him the total number of Coins he gained from Rias and her peerage.

[Reward distributed!]

[Emotional Rewards:

Joy: 1000 Coins

Thrill: 500 Coins

Sense of accomplishment: 250 Coins

Curiosity: 100 Coins]

Cain had to read the information several times to understand what he was seeing. There were a total of 5 people entering the dungeon and they got a total of 1,850 Coins.

It was much more than what he thought. If he were to get this much money every time, he would have no problems maintaining the dungeon or upgrading it. But, of course, there was no way people would enter the dungeon every single day.

The reason he got such a huge sum of coins today was probably because it was their first visit, and that's why the excitement, joy, thrill and curiosity. The sense of accomplishment, however...

He opened up the system and checked his stats. There were several options available to him, like managing the monsters, items drop, dungeon floors, etc. But for now, he just wanted to check how much Coins he had earned from this group.

The amount displayed in the screen showed him that he currently had 2350 Coins in his possession, meaning he earned around 500 more Coins after the notification.

"This is great. Making a dungeon is fun!" Cain said.

He had spent a lot of his Coins on making this first floor. He wanted to see what kind of reaction the adventurers would have once they entered his dungeon and what kind of things he needed to do to improve the experience for everyone.

Now that the dungeon's first trial was completed, Cain wondered how to expand his dungeon.

"I should make another floor..." Cain muttered.

But before that, he watched how Rias' group reacted to the blue portal that suddenly appeared alongside a message window.

[Congratulations! You have finished the Fun Fun Dungeon first floor!]

[Because you chose the boss room, you can't advance to the 2nd floor! Please enter again when the cooldown reset.]

[Cooldown: 3 Days.]

The notification window appeared before the six people in front of a blue portal. Everyone stared at the window before they looked at each other. Then, one by one, their faces broke into grins and they began laughing.

"Did you guys hear that? We beat it!" Issei exclaimed excitedly. His eyes were sparkling. He seemed like he was ready to celebrate right away, but he quickly stopped himself when he saw Rias looking serious. She turned towards her friends with an expression that made everyone else stop smiling immediately. She spoke quietly yet firmly.

"I am satisfied. But this isn't enough for us to understand this place. We don't even know who or what is the creator of this place." Rias looked at her comrades seriously. "Let's take a break. After three days, we will come again and look around the second floor. This portal should be the exit."

Rias turned around and stepped forward. As she did so, a blue light engulfed her body and teleported her out of the room. Akeno, Kiba, Koneko, and Issei all exchanged looks, wondering whether or not they should follow their leader. After a moment, Akeno smiled gently and nodded to the others.

They walked through the blue portal and disappeared.

Only when the room was empty, the portal disappeared and Cain sighed.

"That was fun. Now that I have more coins, I can create a better trap and more monsters. Hehehe, maybe I can make a fan-service dungeon too in the future." Cain rubbed his chin as he thought of various ideas.

Based on what the system told him, he could connect more worlds in the future. Not only that, he could make more dungeons or copy the entrance to appear in different places too!

"Maybe characters from one anime can meet with another in my dungeon? Oh, I am getting excited. What if Rias meets with devils from another world like Vergil or Dante? Or what if Aqua from Konosuba met with other Gods? Oh, maybe The Hunter from Bloodborne met with Geralt from The Witcher?"

Many exciting characters to play around, many ideas that could be used to farm coins, many ways to enjoy this new life of his.

"I'm looking forward to the future. Hehehehehe."

He was a nerd, and he loved anime and manga. Now he was in charge of making a world that would entertain the worlds he loved.

Who didn't get excited over that?

"It's time to work!"

Back in the old school building, everyone gathered at the Occult Research Club room.

"What do you think, Akeno?" Rias asked, she sat on the club's president seat while Akeno brought her tea. She drank it slowly as she looked at her queen who sat on the seat across from her.

Akeno tilted her head slightly and said, "Hmm... To be honest, I have no idea. This is the first time I've ever seen something like this, so it's hard to say for sure. But isn't that similar to a game?" she mused.

"I agree. I feel the same way. Is there anyone else besides you two who knows about this game?"

"Ise, what about you? Have you played a game like this before?" Kiba turned towards Issei, hoping he could help answer their question.

"Umm... Well, yes. I have played games where you need to explore dungeons, defeat monsters and bosses, get items and treasures. But this is real! How could something like this happen?" Issei scratched his head and looked confused.

"This is the real world." Rias nodded and then added, "And we're not dealing with humans. It's a supernatural occurrence, which makes it all the more strange."

She put her hand on her chin and pondered over this mystery.

"Unlike the game, we also don't get a reward for killing the boss..." Koneko said as she took a rice cracker from her pocket and munched it down.

"Yeah, you're right. I expected a treasure chest or something after defeating the boss, but nothing came out." Issei sighed in disappointment. He had hoped that he could gain some loot or rare item drops. "President! Maybe we will find the answer if we beat the second floor! The doors at the end of the first floor must be an option! We chose the wrong choice, right?"

"That might be it, Ise." Rias smiled at him.

The door to the room suddenly opened and a young girl stepped inside. She was wearing the Kuoh Academy uniform, but unlike Rias, her hair was pure black instead of the red color. Her glasses were a perfect match for her serious face.

"Rias." The girl, the student council president of Kuoh Academy, Sona Sitri, said in greeting.

"Sona." Rias stood up, smiling as she greeted the younger girl.

"Do I need to ask or will you explain what's going on?" She glanced over to the other devils. Rias sighed softly.

"I was waiting for you to come here. Let's discuss the dungeon behind this old school building. We're still trying to find out what it is."