Reincarnated in the World of High School DxD

'The moon looks like it's bathed in blood...'

Kazuki Fuwa, a third-year student at Kuoh Academy, muttered to himself as he stared up at the crimson full moon on his way home from a part-time job.

Kazuki was born and raised in Kuoh Town. Until he was ten, life was peaceful, but tragedy struck when his father was transferred to another city for work.

While settling into their new life, his parents were killed in a horrific car accident. A drowsy truck driver plowed into their bus, resulting in the deaths of all ten passengers on board.

Left orphaned and with no time to grieve, Kazuki was taken in by his paternal grandfather, the only family he had left.

His grandfather was a martial artist, a solitary hermit living in the mountains, and dedicated to his craft.

From the day Kazuki arrived, he was thrown headfirst into grueling martial arts training.

The harsh regimen often pushed him to the brink, and while any sane person would question putting a mourning child through such torment, it left Kazuki no time to wallow in sadness. The days flew by, filled with nothing but sweat, bruises, and pain.

Five years passed in the blink of an eye.

At fifteen, Kazuki had honed his skills enough to occasionally outmaneuver his grandfather in sparring matches.

Although, according to the old man, he still had a long way to go. With this milestone, Kazuki was finally allowed to leave his grandfather's tutelage.

After graduating middle school—a school so remote it only had three students—Kazuki returned to Kuoh Town, his birthplace, and enrolled in high school.

Fortunately, his grandfather had managed his parents' inheritance, leaving Kazuki enough money to live comfortably through college if he was frugal.

Grateful to both his parents and grandfather, he started a new chapter of his life.

Settling back into his old apartment, he took the entrance exam for Kuoh Academy, a prestigious local private school, and passed with flying colors.

In April, Kazuki found himself in Class 1-A at Kuoh Academy.

The school, originally a girls-only institution, had recently opened its doors to male students, which meant the overwhelming majority of students were still female.

To his surprise, his class included two of the school's most renowned beauties: Rias Gremory, with her flowing crimson hair and piercing blue eyes, and Akeno Himejima, whose raven ponytail and amethyst eyes radiated a mature allure.

Although both were 15 years old, they boasted beauty and outstanding proportions that put adults to shame, and their breasts in particular were so big they could be called gigantic. 

The first time Kazuki saw them, he was so captivated he couldn't even blink.

As his high school life began, Kazuki opted out of joining any clubs, focusing instead on a part-time job to support himself.

His years of living in isolation with his grandfather had left him awkward and quiet, and he quickly earned a reputation as the "Silent Guy" in class.

Despite this, his classmates treated him kindly, and he managed to make a few friends. Life at Kuoh Academy was ordinary and enjoyable.

Days passed by and before he knew it, Kazuki was a third-year student in Class 3-A.

Remarkably, Rias and Akeno, now dubbed the "Two Big Sisters of the Academy," were still his classmates for the third year in a row. He counted himself lucky to be surrounded by such gorgeous, big busty girls.

Kazuki thought his days of peace and routine would continue, but he couldn't have been more wrong.

It was late at night when Kazuki finished his part-time shift and hurried back home.

The blood-stained red full moon overhead made his skin crawl with unease.

Hoping to shake the feeling, he decided to take a shortcut—a route that passed by an abandoned church.

This church brought back memories of his late mother, a devout Christian who used to drag him to Sunday Mass.

He also recalled the pastor's tomboyish daughter, a girl who always called him "Kaz-nii" and adored him like a big brother. She had moved to England years ago, and Kazuki had no idea where life had taken her since.

The church itself, having been left without a caretaker, was now a desolate ruin.

As Kazuki stood reminiscing, a blinding light erupted from the church, followed by a deafening explosion that shook the ground beneath him. Startled, he crouched instinctively. The light and sound vanished as quickly as they had come, leaving the church eerily silent once more.

Just as Kazuki decided to leave, the sound of something crashing echoed from within. A figure burst out of the church, stumbling toward him.

It was a woman, her sultry outfit torn and tattered. Behind her, a pair of ragged black wings spread weakly.

'What the fuck is this? A movie shoot or something?'

Before he could process what he was seeing, the woman snarled, "Out of my way, asshole!" and raised her right hand toward him.

Her once beautiful face was twisted with madness and fear, and in an instant, her hand plunged through Kazuki's chest with a sickening thud.

But Kazuki wasn't some helpless bystander. His body, honed through years of brutal training, reacted on instinct. Driven by reflex, he struck back.

"Gaahh!?"

The woman, clearly not expecting any resistance, took Kazuki's counterattack—a powerful punch—to the face and was sent flying.

"...Ugh!"

But that was all Kazuki could muster. Overwhelmed by the pain and blood loss, he coughed up a mouthful of crimson before collapsing onto the ground.

Everything faded to black. The world around him was silent save for distant, frantic voices.

"Damn it! This bastard's tenacious! Just die already!" the woman shouted

Then a blood-curdling scream echoed—

"Yuuma-chan… no, damn it!"

"President! Someone's collapsed here!"

"What?! How did they get inside the barrier?"

"...! Rias, this person…"

"What is it, Akeno? ...No way! Why is he here of all places?!"

"President, do you know him?"

"...Yes, he's a classmate."

"What do we do, President?"

"There's no choice, Akeno. Let's do this!"

"Yes, ma'am!"

Kazuki could barely make sense of the voices surrounding him. Some sounded vaguely familiar, while others were entirely foreign.

Then, a peculiar sensation overtook him—a warmth that began to seep into his broken, bloody body.

His eyelids fluttered open slightly, his hazy vision capturing nothing but a radiant shade of crimson.

The next morning—

Kazuki Fuwa jolted awake, his heart racing.

He was in his bedroom—his own, familiar bed. But as his eyes adjusted, he noticed something horrifying and surreal: a naked woman was lying next to him.

And not just any woman.

Rias Gremory.

Kazuki's heart pounded in his chest, practically deafening in his ears. His eyes trailed over her flawless, milky skin, her fiery red hair cascading like waves across his pillow.

Even in her sleep, she looked impossibly beautiful, her youthful innocence tinged with an almost unnatural allure, she looked like a goddess.

Her bare shoulders shifted slightly, and though she was lying on her side, her ample enormous breasts didn't sag in the slightest, the perfect curves leaving little to the imagination and hard to believe she was 17.

'What the hell? What's going on?!'

Kazuki's mind raced as he tried to piece together the events of the previous night.

'Have I... lost my virginity? Did I… seriously sleep with Rias fucking Gremory and somehow forget it?! If so, what kind of idiot would let something like that slip by without remembering every second?!'

As he drowned in his panicked thoughts, Rias stirred beside him. "Mmm... morning already...?"

Kazuki froze. Her sleepy, half-lidded eyes met his, and she sat up slowly, rubbing her face.

The sheet covering her fell off, revealing her full, unrestrained form. Her large voluptuous breasts were completely exposed, their soft pink tips standing out against her porcelain skin.

Kazuki gulped audibly, his throat dry.

Still groggy, Rias reached out and placed a hand on his abdomen. Her touch was cool against his skin, sending shivers up his spine as her fingers moved carefully, almost methodically.

After a moment of silent examination, she sighed in relief; "Good. The wound's completely healed. How are you feeling, Kazuki Fuwa?"

"I-I think I'm fine...?" Kazuki stammered, trying and failing to keep his eyes from wandering.

"That's a relief," Rias said with a small smile before her expression turned serious. "I suppose I owe you an explanation. How much do you remember about last night?"

Kazuki racked his brain. "Let's see... I passed by the church, there was this crazy bright light and a deafening explosion. Then some woman wearing... uh, revealing clothes attacked me. I fought back but blacked out after that."

"Oh my," Rias mused, her tone equal parts impressed and amused. "You managed to fight back? Even with a hole in your stomach? You're tougher than you look."

"A... a hole?" Kazuki looked down at his abdomen in shock. His shirtless torso looked perfectly normal—no scars, no blood, nothing.

"I told you, didn't I?" Rias said with a chuckle. "The wound's gone. I healed it by transferring some of my magic to you. That's something only I can do because..."

Her expression softened as she locked eyes with him.

"You're one of my servants now. My pawn. You belong to me, Kazuki Fuwa."

Bottom of Form

"I told you, didn't I? The wound's been sealed. I didn't have enough magic, so I gave you some of mine to heal it. It's something I could do because you're my subordinate."

"Magic? Subordinate?" He didn't really understand what she meant.

Maybe Rias noticed the confusion on his face, because she stood up from the bed and turned her back to him.

Her crimson hair stood out against her flawless white back, creating a truly beautiful sight. Her round, firm buttocks were in full view, exuding unbridled sexiness. He couldn't help but stare, and in the next instant, black wings spread out from her back.

"—Huh?"

Those bat-like wings evoked a certain image. It was like—

"Now, do you understand? I'm a devil."

She revealed her true identity. And then, she uttered another shocking line.

"And you, Kazuki Fuwa, starting today, you're one of my servants. That means you're a devil now."

Afterward, Kazuki received an explanation from Rias Gremory.

This world was ruled by three great powers, angels, demons, and fallen angels, who were fighting for supremacy.

However, a war that occurred long ago caused a large number of casualties for all three powers, and they were in a situation where they could barely maintain their power.

As a result, large-scale wars couldn't happen anymore, and now only small skirmishes occurred.

The devil side had been reviving their power by giving humans a special item called the "Evil Piece," which would reincarnate them as devils.

The "Evil Pieces" were magical items resembling chess pieces. The high-ranking devils, like Kings, would give them to humans and make them their subordinates. Each piece had its own role to play.

Kazuki's piece was the "Pawn," the weakest piece in the Evil Pieces or the so-called CHESS. In other words, his "King" was her, Rias Gremory, and he had become her servant.

"I had no choice but to do this to save you. I'm sorry for letting that fallen angel escape because of our carelessness."

"No, I didn't want to die either, so it's fine. In fact, I feel bad that you had to use such a valuable piece..."

"Fufu Thank you. You're really a good person, Kazuki. And I don't regret making you my subordinate!"

Rias flashed a dazzling smile, and Kazuki couldn't help but feel a warmth in his chest.

"Did you know me, Rias-san? I meant before this…" Kazuki asked curiously, and she answered, smiling.

"We were in the same class for three years!! You weren't exactly the most noticeable, but when there were tough times like during the cultural festival, you always stepped up to help. I noticed you." Rias said.

"Well, I didn't know you were paying attention like that..." Kazuki felt a surprising joy at her having noticed him.

Just then—

"Ugh!?" A sudden headache hit him and Kazuki nearly collapsed.

However, Rias caught him, and his face was buried in the soft, fragrant cushion of her chest. Realizing what was happening, his face turned red.

"S-Sorry!" he said.

"Don't worry about it. It seems you're still not fully recovered. Just rest for a bit more." She gently laid him back down on the bed.

"Luckily, it's Sunday. Just sleep for now. We'll talk more tomorrow at school."

"Yeah... Sorry..."

And with that, he fell into a deep sleep.