Fate/Purgatory

Disclaimer: The original story, elements, and characters of High School DxD and of Nasuverse belongs to Ishibumi Ichiei and Kinoko Nasu respectively. Any other elements and characters that may appeared in this fic belongs to their respective owners. I only own this plot and any original characters within this story.

AN: Alright! Welcome to another chapter of Fate/Purgatory, guys! Thank you so much for wasting your time reading this story and especially for those who bothered to waste more time writing the reviews since it made my day. Oh yes, I got a review from some guess reader who thought my OC as Shirō. Please do not I mistake him for Emiya Shirō, especially when I don't particularly (read: really don't) like him. There is Emiya Shirō in this fic, after all I made DxD universe and the Nasuverse into one with rules that are more in line with Nasuverse rather than DxD, but I don't think I would give him a role, or even if I did, it would be a minor one or I would just arrange something to have him killed so all readers who thought my OC as Emiya Shirō would shut up. Right, onto the story then!

–Fate/Purgatory–

Chapter 1

Quaint was the word Kotomine Kai thought of when he saw the church his superior told him to head to. The building itself was neither too grand nor small, but the whole complex was actually quite large. The architecture was clearly old fashioned, but it has unexplainable pleasing quality that he had long associated with church buildings. The church was perhaps large enough to house 100 or so people. It was quite unusual for a church to be that big in Japan, especially since Christian is a very small minority in the country. He supposed there were enough Christian in the city to require a large enough church.

"Time for intel gathering, I guess," he muttered to himself and knocked on the door of the church.

The door was opened by a young nun, only a few years older than himself from her looks. The day was still quite early for any visitors, but she didn't seem to be surprised when she saw him.

"Father Kotomine, I presume?" She asked him.

"Indeed." Kai nodded in confirmation. "I'm guessing you're the caretaker of this church?"

The nun shook her head. "No, that would be Father Ayasegawa. I'm just one of the nuns tasked by the bishop of diocese to help him in taking care of this church."

"I see," he said, accepting the answer. "May I know your name, then?"

"My name is Okita Shizuka, Father," she bowed to which Kai replied in the same manner.

"Kotomine Kai. Pleased to meet you."

She nodded courteously then signed him to enter the church. "Father Ayasegawa is waiting for you. Please follow me."

The nun led him to a small room where a priest was praying in silence.

"Father Ayasegawa?" the nun called. "Father Kotomine is here to see you."

The priest finished his prayer quietly before stood up and turned to face them. He was a man in his fifties with hair that already greyed.

"Father Kotomine," he greeted with a bow. "My name is Ayasegawa Hiko. I have been informed by the Vatican that you would come. Welcome to Church of Misaki town."

"Glad to be here," Kai bowed back, but his expression was impassive as ever. "I presume you know why I'm here?"

He shook his head. "The Vatican did not disclose anything to me, but I was once an Executor years ago and I recognize the black cross on your left sleeve. I am aware of their reputation and what kind of mission they have, so I would imagine that you are here for someone."

"The fallen Holy Maiden, Asia Argento," Kai replied in affirmation. "She was reported to be somewhere in Kuō town from our intel."

"I see," he said solemnly, though he couldn't hide a hint of sadness behind his tone. "I met her once when I was stationed in Italy. She was a kind girl, one who was truly pure-hearted. A rarity in this world influenced by darkness."

"It is a shame," Kai agreed in neutral tone. "But I have my order. The higher ups said that you were responsible for keeping eyes on the Kuō town due to possible Devils presence there. Can you confirm her presence in the town?"

The elder man nodded in affirmation. "Yes. Sister Okita here reported to me that she saw her walking around the town, asking for the location of the abandoned church there. She also confirmed the presence of three low-class Fallen Angels along with fifty or so rogue Exorcists stationed at the mentioned church."

Kai turned to look at the nun who answered his questioning glance with a firm nod. "I see. What about the Devils? Can you confirm their presence in town?" he asked.

Father Ayasegawa looked nervous when he asked this, as did the young nun. They glanced at each other for a moment before the old priest spoke, "Yes, but their identity that makes it a problem."

Kai didn't react at all to that words. Bad news is just another day at the office for him, so he simply signed them to continue.

The elder priest handed him a folder instead of replying. He silently opened it and read the content before a small frown appeared on his face. "I see. That's problematic," his voice betrayed no emotion. Kai closed his eyes for a moment, silently contemplating his next move. Deciding that further consideration is needed in the light of information he had received, he requested to stay in the church for the night, which they granted. He was then led by the young nun into a room within the complex.

"This is your room, Father," sister Okita told him, showing him a spare guest room.

"Thank you for your hospitality, sister," Kai bowed to her in a polite grateful manner though neither his face nor his voice gave anything but impassiveness.

"It's my pleasure to help you, Father," she said politely, though Kai could tell that she was actually nervous behind that polite facade. "If you need anything more, please don't hesitate to ask me or any of the nun. We will be happy to help you." And with that, she left him to his rest.

Silently closing the door behind him, Kai changed his travelling outfit into a more comfortable casual one. He then lit up a candle before he took a seat in meditative position in silence. This mission had turned out to be more difficult than he thought. The objective itself was not that difficult, but completing it would be quite tricky considering what intel had reported about the town. Still, it could work to his advantage should he was able to handle it correctly. And whether it would go smoothly or not, it would not change the outcome.

For Hyōdō Issei, words such as "friends," "family," "comrades," or "close/precious person" meant nothing to him. For as long as he could remember, which stretched back to about seven years ago since he can't remember further than that thanks to his amnesia, he was always alone.

Oh, he was not an orphan as he still had his parents. It's just that they were… distant, to put it mildly. He wasn't blind. He could see that his parents were scared of him despite them trying their best to show that they loved him. He deducted that whatever had caused them to act like that, it was connected to the incident that caused him to lose his memories, judging from their happy family photographs that was taken before the incident. Whatever happened at the time, it made his parents terrified of him as if he was not human, as if he was a… freak.

His school life was equally secluded. He never had or made any friends throughout his years at school, not that he bother to try. His reputation as a delinquent who could, and had, sent an entire gang to the hospital by himself ensured that he was feared by other students, enough that they would sooner stay away rather than being his partner in a school project. His teachers were just as frightened of him. Ever since he put that one gang to the hospital, they avoided him like a plague and won't talk or even call him in the class unless it was absolutely necessary.

Simply put, loneliness was the life of one Hyōdō Issei. That was all he ever knew, and he wasn't bothered about it. He'd never expect anything more or less in his life than what he already had and what he wanted. And companionship was never either one of them.

Today, Issei skipped the school again. He was strolling around the town as usual when he wasn't in the mood for school to clear his mind. One could say that this was his favorite past time since no one would bother him when he was strolling around. People were too busy minding their own business to pay attention to him, so he was free to do whatever he wanted. But then, he spotted one of those gang whom he had put into hospital once for trying to make him pay "taxes." Within his own bloody territory. They were chatting up to a girl, a foreigner by the look of it, since she had long blonde hair that could be easily spotted even beneath the veil she wore. When he observed the girl, he noted that she seemed not to notice the lecherous face they made when they chatted to her and she even naively believed that they would help her so generously in her endeavor.

Now, normally he would silently follow them to make sure that the girl would be okay as he had no illusion of what their intention toward her, and his only reason to do so would be that he didn't like anyone not playing by his rule within his territory. It would have nothing significant to do with the girl. But somehow, this girl was different.

He could feel something in his gut gnawing at him to rip those gang apart for trying to harm the girl. For trying to harm what's his. This sudden bout of possessiveness confused him. He had never feel something like it before. Before, he was content with what he already had. Now, he felt the need to stake his claim for the girl.

He followed them from afar as he pondered upon this strange possessiveness until they finally arrived at an abandoned warehouse on the edge of town. The gang 'asked' the nun to have 'fun' with them, but apparently the nun finally realized of their intention and tried to run away to no avail as the members quickly trapped her, preventing her from escape. He was about to interfere when a literal, honest-to-god, bloody monster appeared all of sudden.

If you only looked at its face and upper torso, you would probably think it was a naked young woman who was abnormally tall, but the lower part of its body was what showed its true nature; it was gigantic and beastly with four legs, bearing heavy resemblance to some kind of mutated lion or something. However, Issei could care less about its appearance. What's intrigued him was how the aura it exuded affect him. It felt dark and inhuman, but most of all, utterly inferior. The sheer inferiority of it evoke a sense of disgust in him, made him sneer at the pure arrogance of this pathetic being that deluded itself as a superior existence.

Issei didn't even bat an eyelid when the monster wannabe slaughtered the gang members in bloody gore and eat their corpses. He was too busy pondering upon the pure amusement he felt when he watched the brutal massacre. He didn't feel utterly horrified, scared, or any of its equivalent as a human being supposed to be when they faced a monster. Instead, he's getting a sense of glee watching a so-called monster massacred a group of lowly scum like humans watching a predator eating its preys in a setup they made.

That thought made him paused a bit. Since when he no longer considered himself human? What had made him to think that he was superior compared to this… beast in the first place? Weird did not even start to describe what he felt, but something inside him knew it wasn't an arrogant claim. It was fact.

His mind was snapped from the train of thought when he heard the girl cried in fear and desperation when the wretched beast setting its sight upon her, its eyes gleamed in predatory hunger. The sight of it made his blood boiling. The nerve this lowly beast trying to claim what's his! For the first time after years of unfeeling coldness with bouts of passing bloodlust and glee that fade to nothing in mere moments, Issei truly felt something; pure, unadulterated rage accompanied by a murderous desire to utterly crush the beast.

Massive waves of monstrous red aura exuded from his body as Issei set his sight upon the beast who suddenly went still with looks of pure terror in its eyes when it spotted him. In mere blink of an eye, Issei was already upon it as he charged a punch with his left arm which was covered with red scaly gauntlet that he had no idea where it came from or when it even appeared. That single strike upon the beast annihilate it with explosion of menacing red aura, removing even the slightest trace of its existence along with its victims.

The world went silent for a moment after the beast was gone. Neither him, the nun, or even the world made a single sound to be heard. But then, he began to laugh. Laughter that held both joy and contempt, relief and bitterness over reality that almost sounded insane. For Issei, this was the revelation. Now he understood why his parents feared him, giving the look that said he was anything but human. Why he simply couldn't relate to others around him. The answer had always been right in front of him all along. He was just too blind, too naïve to see it.

He's not a human. He may looked like one, but within, he's anything but. What else that could explain his detachment, his power, his inhuman thirst for fight and blood, for total domination?

"Dragon…" something inside him whispered that word. Yes. That word fitted him down to the core. He may looked human, but he was a Dragon through and through.

Suddenly, a small, almost unnoticeable 'thud' and an admittedly cute yelp behind him caught his attention and he turned to see the young nun fell on her ass, her green eyes were all watery as her backside stinging from the pain.

Feeling a stare on her, the nun looked up to find her savior was looking straight at her with those fierce brown eyes that unnerved her greatly, but at the same time feels soothing. A contradiction which greatly confuse her. However, being the good, naïve nun she is, she decided to trust him, especially since he saved her from the monster that almost killed her.

"T-thank you for saving me, mister…?" her stutter faded at the end and her face scrunched in genuine confusion even though Issei could still pick up the fear on those innocent green eyes clear as day.

Issei opened his mouth to answer her unspoken question when suddenly his instinct flared up, warning him to immediately leave as he, somehow, sensed multiple presence approaching. None were threatening enough individually, but they were definitely stronger than the beast he'd just thrashed and with their number they have potential to be quite an annoyance. Especially with the nun around. He made up his mind instantly to follow his instinct and get clear of the area, bringing the nun with him. The thing is, with how quick the presence approaching the warehouse, he would not be able to, much as he hated the word, escape in time with the nun.

"Use my power to… get away, boy." An inhuman voice whispered to him. Something about it giving off aura of great, and terrible, power. Something ancient beyond belief. Suddenly, the previous red aura exuded from him again as it spoke. It filled his head with a thousand questions, but now was not the time to get the answer. He got no alternative, so he decided to follow it, risky as it was. Instinctively, the image of his room appeared on his mind, the first place he had in mind to hide. He felt the read aura spiked and quickly grabbed the nun before the world gone in red haze. The last thing he saw before the world was completely drowned in red was a strange red circle with a crest on its center that gave off similar inhuman dark aura to the beast, unaware that as he gone, a pair of cold blue eyes had been observing them since the very beginning.

Kotomine Kai stood calmly on the roof of nearby house, observing the group of Devils who turned up at the warehouse, undoubtedly attracted by the aura of power the brown-haired boy gave off. He assessed each of them carefully, judging their potential threat based on the aura they exuded. Several among the group in particular caught his attention.

"Heiress of the Gremory and the Sitri. Sisters to the current Lucifer and Leviathan," he mentally noted on the redheaded girl with bluish green eyes and another glasses-wearing girl with short black hair and violet eyes. His eyes then turned to the other Devils.

"Mostly consists of normal humans with rather high magical potential. Three Sacred Gear possessors: the boy with dragonic aura, the girl with long black hair and glasses, and lastly," he paused a bit as he identified the last girl whom he was quite familiar with in the past. "Izumi. Survivor of Valper Gallilei's Holy Sword Project. Possessor of a high-tier demonic-type, Sword Birth."

"Two non-human reincarnated. A Fallen, or perhaps a Nephilim," here he briefly looked at the girl with long ponytail before turning to a small, white-haired girl who looked like she belong to middle school or perhaps the elementary. "And a Yōkai. Nekomata."

Kai never moved from his place as he continued watching the Devils trying in vain to find the source of the previous power surge, or at least a trace or clue that allows them to identify the source and where they had gone.

Seemingly frustrated on the fruitless search, the Devils cleaned up the whole mess before leaving with their Magic Circle. Their leaving prompted Kai to approach the warehouse.

The Devils had done a fine job to clean the mess from wandering human eyes. Normal human eyes that is. For those who were experienced in the supernatural world, it's not even close to 'decent.' The slight leftover of magical signature would be easily picked up by anyone with enough experience.

He pondered upon the scene he had witnessed before the arrival of the Devils. The brown-haired boy exuded a powerful red aura unlike anything he'd ever felt before. So powerful that even the slight trace remained on the scene brought a chill on his spine as it screamed for absolute domination. Aura which has the distinct signature belongs to the Dragonkin.

Red. Domination. Dragon.

His normally passive blue eyes widened slightly as realization hit him. "The Welsh Dragon…" he whispered the words unconsciously.

There was no doubt about it. The brown-haired boy, whoever he was, had unknowingly become a major player in the world of supernatural. Just like his predecessors had been as the possessor of the infamous Red Dragon Emperor's Gauntlet. One of the thirteen Longinus which could kill even God.

This revelation brought a brief smile tugged on his lips. A smile which almost… insane. Filled with such a thirst to see blood spilled. To watch the world burn till nothing left remained. Not even the ashes. His blue eyes was glowing with unquenchable fire that threatened to consume anything, everything.

Kai suddenly gritted his teeth and clenched his eyes shut, trying to suppress his more… extreme tendencies. This mission was too important and he cannot risk it, no matter what. Slowly but surely, he managed to assert complete control. With his passive expression back in place, Kai left the premise without further ado. No sense in staying longer that he needed to.

After all, he got a mission to complete.