Shirou knew something was going to go wrong, especially with how everything was going relatively smoothly after they defeated The Demon God Pillar Goetia with the help of every Heroic Spirit they came into contact with and contracted. His luck just wouldn't let anything be left peacefully.

The 28 year old ducked his head as an explosion went off. He and everyone else weren't expecting for them to be attacked soon after every Heroic Spirit returned to the Throne after they saved humanity, but here they were. Shirou looked down to his hands and took note that he only had one more shot left with his Broken Phantasm crossbow, which he made after he found it would take a Servant's level of strength to draw the black bow EMIYA uses.

'God damnit…! Who the hell are these bastards! It hasn't even been a week since we restored Humanity and there is already a group ready to kill us!' Shirou screamed mentally as he slid around a corner.

"Come on Shirou-nii!" Ritsuka screamed at him.

Ritsuka Fujimaru, one of the last two masters of humanity was running alongside Shirou, both of them trying to get to their escape point. The younger teen looked up to Emiya as though he were an older brother in their time saving humanity. The black haired teen ran forward to grab a door as Shirou spun around and Traced a simple sword, flooded it with prana and threw it.

"Who the fuck are these guys?!" Ritsuka panicked.

"The hell if I know, just keep running!" Shirou shouted, pushing Ritsuka away from the door.

The pair continue to run through the destroyed halls of Chaldea, dragging along any staff members that they can find. As they began to reach their escape, the explosions began to get worse, indicating that the enemy was almost on top of them.

'Looks like one of us isn't making it out of this… I know that the logical thing to do would be to push Ritsuka towards the enemy and escape for myself as I would be the better choice to live… but that is something I would never be able to live with…'

"Looks like this is it Ritsuka." Shirou suddenly said out loud.

"What… Do you mean… Shirou-nii?" The black haired teen asked while panting for breath.

"You go on ahead, I'll buy you all some time." The man responded, lifting his crossbow.

"No! You'll die nii-san!" The younger teen called out to his older 'brother'.

"I understand that kiddo. If my death means that you can live on then so be it. I've already achieved my dream, you have barely even started your life yet." Shirou responded with a small smile.

'Don't look at me with those tearful eyes, little brother. I know you'll do great things with your life.' Shirou thought to himself as he handed Ritsuka a red gem.

"Huh? What's this nii-san?" The boy asked, looking at the gem.

"Something for you to remember me by. Don't pity me little brother, let me go out as a warrior. Don't mourn my loss, celebrate the fact that I lived saving as many as I could, including you." Shirou spoke, inspiring Ritsuka and causing the younger boy to tear up.

"Okay Shirou-nii… I'll celebrate your life… give them hell." The black haired teen said tearfully, taking the gem and turning around.

Shirou watched for a moment as the rest of the Chaldea staff that was with them fled as fast as they could without tripping each other up, before he turned around, hearing the enemy get closer. He shouldered his crossbow, loaded with a Caladbolg II arrow-sword, ready to fire when he could no longer 'smell' Ritsuka in the facility.

'Looks like this is the end of the road for me.' Shirou thought to himself as he placed his finger around the trigger.

As the footsteps got louder and the shadows grew closer, Shirou started to pour prana into Caladbolg II, causing red energy to begin flowing along the tip and cracks to appear in the steel.

"My core is twisted in madness."

As Shirou pulled the trigger he screamed, "CALADBOLG!"

The sword-arrow flew from the crossbow, down the hall at lightspeed and impacted the wall, detonating what was essentially a magical nuclear bomb, wiping out the entire facility in the blink of an eye. Shirou only had enough time to give a soft smile that was full of pain but also full of acceptance and happiness, happiness that he got to complete his dream and also die saving someone he considered a little brother.

XXX

Age: Newborn

Steel coloured eyes opened, revealing a hospital room as their surroundings.

"Oh look dear, he has your eyes." A female voice spoke up, sounding awed.

"And he has your hair too, my darling." A male voice responded with a smile, judging by the way he sounded.

The steel eyed child looked around, his vision blurry and taking a moment to focus before he saw a man and a woman.

The man had the same steel coloured eyes as the baby, and he also had black hair tied up in a ponytail, he had sharp features, though they were still warm when looking at the baby. The woman had auburn hair that fell to her shoulders and icy blue eyes. Her features were also soft but she held a certain steel behind her eyes as she looked at the baby in her arms.

"What are we going to name him Mariane?" The man asked with a soft smile.

"Shirou, his name shall be Shirou Malthus." The woman responded with a similar smile.

'Malthus…? Isn't that one of the 72 demons from Ars Goetia…? Why am I involved in demon shit again, I already killed Goetia…' Shirou, the baby with memories of a past life, thought sleepily.

"Oh look at him, he's tired." The woman, Mariane, said with a whisper to not disturb Shirou.

Shirou closed his eyes in exhaustion, falling asleep shortly after in the arms of Mariane.

XXX

Age: 5

After five years of living with his new family, Shirou came to accept his reality. The fact of the matter was that he was born into a new world as the heir to the Malthus devil clan. At first he was weary about interacting with anyone, even his new parents, due to his experiences with Goetia in the past. But they managed to break through to him and show him that they aren't all like what he had to deal with in his past, with him coming to love them as a child should their parents.

Since he was also now five years old in this life, his father thought that it would be a good time to try and teach him how to forge magical weapons and armor, which is what's happening right now. Shirou and his father Isamu Malthus were standing in the forge on his family's lands, with the older man demonstrating to his son how to hammer away at metal and fuse it with mana.

Shirou watched the whole process, enraptured as he could feel the sword itself being born. He found it a little weird but remembered that every other sword that he could feel and sympathize with had already been through a lot of history, this was the first time he was watching a sword being created.

"And that, my dear boy, is how you forge a sword." Isamu said as he cooled the sword before turning to his son, "What do you think Shirou?"

"The sword itself is calling out for it to find its wielder." Shirou noted to his father.

"Oh? How do you figure that?" Isamu asked his son, intrigued at what he had to say.

Shirou nodded before speaking, "I have an uncanny affinity for swords, to the point where I can read its composition and history with a glance with the blueprint being stored in my head. I can tell that there is a lightning enchantment on the blade, alongside an enchantment that helps the chosen wielder find it."

"That is correct Shirou, I did put those enchantments onto the blade, but what do you mean by your affinity for swords? And then being stored in your head?" Isamu asked with a confused frown.

"Can I trust that you won't tell anyone what I'll show you father?" Shirou asked, seriously, about his use of 'father' and not 'old man'.

Isamu sighed before speaking, "I can tell this is serious Shirou, I promise on my name, Isamu Malthus, that anything said in this room will not be brought up without your permission."

Shirou nodded to his father before walking over to him and taking his hand and focusing on his Reality Marble. Shirou found that he was able to visit his Reality Marble with anyone he wished while their body remained in the real world as long as he held contact with them before transporting them.

Isamus' eyes opened to a stunning sight. All around him were blades, ranging from shortswords, bastard swords, zweihanders, to even halberds, axes and spears. The landscape was a beautiful green grassy hill with gorgeous white and purple flowers growing along the ground, the sky was clear with a blazing sun off in the distance.

"What… is this?" Isamu said in awe.

"This dad is my soul. I know this may sound insane but I am from a different world. I was reincarnated as a newborn after I died in the year 2018." Shirou answered seriously.

"No… I believe you… otherwise there would be no other explanation for all of these weapons, even ones lost or broken are here. How is this possible?" Isamu asked, looking at each blade carefully.

"I don't know entirely. I remember having to work for an organization centered around preserving human history by using time travel of sorts to correct singularities before uncovering that the one behind it was the collective 72 demons from Ars Goetia. Me and one other human fought it with the help of heroes from humanity's past. The last thing that happened after we killed Goetia was that a week after we restored humanity from its incineration, we were attacked by some unknown group. I bought enough time for my comrades to escape before using Caladbolg to destroy the facility."

Isamu was enraptured by his son's story, focusing on the details that were given to him before coming to a conclusion, "Wait Shirou, does that mean every weapon here, you got to see in person?!"

Shirou smiled, glad his father was taking this so well, "Yes, in fact right over there is all the weapons from the knights of the round and King Arthur." Shirou pointed to a collection of weapons.

Isamu looked over and saw a circle of weapons surrounding a sword and sheath in the center of them. He could feel the holy energy radiating off of each weapon, there was Arondight, and a darkened version of it crossed together, to a shield in the shape of a cross with a circle in the middle, to the final swords in the middle, Excalibur and its sheath Avalon.

"What the hell… how does this not hurt you?" Isamu asked as he looked at the swords with interest.

"I'm not entirely sure myself, if I had to guess, I'd say that it is because in my last world I was a sword incarnation with an uncanny ability to sympathize with swords to the point I could feel what they felt. So I guess they are protecting me from their Holy element or something?" Shirou guessed, scratching his head.

"I always knew you were going to grow up big and strong but not this big and strong!" His father wept comically.

Shirou just looked at his father in deadpan before deciding that he had seen enough. He walked over to his father and grabbed hold of him before focusing on leaving his Reality Marble. Soon enough they were back in the forge.

"If you want too dad, we can talk more about my experiences later, after I forge my first sword." Shirou offered with a smile.

His father bounced back and agreed, letting his greatest creation take control of the forge for his first time.

XXX

Age: 10

Shirou had grown up in the last five years, his skills in the forge working under his father have improved greatly, while training in magic with his mother has increased his capacity, allowing him to call upon more weapons quicker and not be as brittle, while his reinforcement grants him strength comparable to that of a high-high class devil compared to his low-high class.

His parents are also aware of his origins completely with the fact that he was born from fire and saved humanity in his world. At first they were a little concerned that it might affect their son to be part of a family from the Ars Goetia, but they found that he adapted quite quickly to being a devil.

They wished that they could stay with him longer, but right at this moment a civil war was happening. The Anti-Satan faction was fighting against the Old Satan faction who wanted to keep the underworld the way it is and still engage the Angels and Fallen Angels despite the heavy losses. His family was wanted by both sides, his father due to his ability to make magically enhanced gear, and his mother for her mutated Phenex trait.

His mothers trait also passed onto him, granting him the healing ability of the Phenex too. He knew that both him and his mother would be in danger due to their traits and so he Traced her a sword that he knew was powerful and gave it to her before his parents ordered him to run away.

He so desperately wanted to stay with them and fight, his old instincts about fighting and defending others coming back, but when he saw their eyes he relented. Their eyes looked as though they wished to stay with him but knew that their time was up, he knew that look well, as he also held it in his final moments. So with a heavy heart he decided to listen to them and run.

Right now he was running through the forest in the direction that he knew Big Sis Sera was, in hopes of scaring off his pursuers. He could smell them getting closer though, the smell of Brimstone, sulfur and other elements mixed in gave away their positions as he was suddenly stopped.

"Come on you brat, enough running!" One of the Old Satan devils shouted at him.

Instead of responding, Shirou Traced nameless swords and launched them in all directions. The swords pierced his attackers and killed a few while others pulled the swords out or ignored them completely. They all began creeping towards Shirou leaking killing intent all directed at him when a sudden flash caught their attention.

The flash blinded them momentarily and when their vision cleared they took a quick look at their surroundings, noting that it looked like they were in some kind of city. Shirou took note of the skyscrapers and other devils using things that looked like phones from his old world.

'That can't be right… we aren't even in the age where humanity started to harness electricity so why are there phones here?' Shirou thought to himself before discarding those thoughts and focusing on his attackers and would be assassins.

The hammer in his head fell and glowing lines flowed down his arms as blue flames started to coalesce in his palms. In a flash there were his married blades in his hands, sliding into the stance that EMIYA and himself made, modified to his shorter stature, Shirou watched as his would-be killers rushed to him.

When the first got close enough to take a swing at him, Shirou parried at the last second. Taking a swing out at the devil in front of him Shirou cleaved clean through his arm and part way through his chest. The first devil fell to the floor screaming, Shirou had to dodge a fireball launched his way before he could finish the first one off.

As Shirou backed away he looked towards the closest devil who was flying about 20 meters away from him. The boy smirked and spread his wings of blue flames and shot forward to the devil. When he was close to him he cut his head clean off and collapsed his wings, falling towards the next devil.

This one was a little more sturdy, with Kanshou only cutting part way into his shoulder and instead of letting out a scream he just grit his teeth and swing his head forwards, impacting Shirou's nose and breaking it. The ten year old staggered away, feeling the heat of his mutated Phenex healing activate and right his nose. Shirou looked up from his crouched position and saw that there were only five left standing.

'This is a pain.' Shirou thought to himself before subtly shifting his stance.

The boy threw both blades at his opponents, spinning through the air like buzzsaws. As his first pair of blades flew through the air, Shirou Traced the first blade he ever saw his father forge, a nameless sword that held lightning in the blade and could be tracked by the wielder. He rushed forwards at the devil who hit him and locked blades with him.

"Give it up brat! You're surrounded and your parents are already dead!" The devil shouted with glee.

Shirou's eyes constricted into pinpricks, and flooded his body with mana. His reinforcement took on a whole new level, comparable to that of prana burst from Artoria Pendragon. Shirou let out a feral scream as he overpowered the devil in front of him.

"Shut up, Shut Up, SHUT UP!" killing intent flooded the air, scaring some of the other assassins into standing still, feeling as though blades were held to their throats.

Shirou could smell a new scent in the air, reminding him of fresh water and winter. A voice called out from behind Shirou in a high pitch.

"How dare you evil doers attack a child! Magical Girl Levi-tan will save you!"

"Shit! Why is the Sitri General here?!" One devil shouted ready to flee.

Shirou ignored the voice and cleaved through the devil that was in front of him. Before he could move onto the next devil assassin, a wave of ice froze the area and all of his attackers. Shirou was bent forward still ready to fight even as he knew they weren't getting out of the ice, his breathing was heavy.

Shirou turned to the person who helped him and was momentarily stunned at who it was. Dressed in what looked similar to Prisma Illya's outfit, Serafall Sitri was standing there.

"Big Sis Sera?" Shirou whispered.

"Shirou?" Serafall whispered, shocked at his appearance.

"Big Sis, what the hell are you wearing?" Shirou blurted out.

Serafall pouted and crossed her arms before responding, "The first thing you say to me after 500 years and it's that?"

Shirou raised a confused brow and responded, "What do you mean 500 years? I literally just left my parents home not even half an hour ago to run to get you to help us."

Serafall looked at Shirou with a sad eye before speaking, "Shi-tan, how about we speak some place else, I don't think that you want to talk about this in public."

"Okay, where are we going?" Shirou asked, adrenaline slowly leaving his system.

"My family's home, I'm sure mother and father would love to see you again. Oh! And I can introduce you to my adorable little So-tan!" Serafall gushed and grabbed Shirou's hand.

A circle with the Sitri family crest appeared underneath their feet and with a flash they were gone.