When Yuusuke was little, the world was small and simple—just his school, his friends, and a tiny plastic rectangle.
It was his first handheld console.
His parents gave it to him, after he was begging for months.
It wasn't much but he had lots of fun playing his favourite games.
By the time he got it, all his friends were already playing on the newest home consoles, laughing about graphics and online multiplayer he couldn't dream of.
But he didn't care. He'd sit on his bed, thumbs tapping away at the scratched buttons under his blanket.
When he got into high school, he worked at a part-time job and after a while of working, he had saved up enough money, to get himself a Computer.
After he got it, he'd fight hollows in Type//Soul and Smash Bros, his favourite game.
His main was Cloud—every forward smash, every move carefully planned out. He even went to tournaments under the username "0graps". He went to nationals and even became the number one.
Then one day, something strange happened.
It was after graduating school, the controller still warm in his hands, when he tried to mimic one of Cloud's sword swings in the mirror for fun. A faint spark, like from electricity, flashed around his body. It was just a fracture of a second but he felt it.
He blinked—and when he looked into his hand, there was a faint, translucent cartridge.
At first he thought everyone could do it. He told his parents at dinner, expecting them to nod like it was normal. Instead, they traded a confused look. No answers. Just fantasy.
Over time, Yuusuke experimented. He learned that each cartridge was a recording—a stored action. He could load it into himself, and in an instant, his body would replay that movement exactly as it had happened.
After some time, he noticed that he could also record movement that wasn't solely executed by him.
He recorded his favorite fight scenes from movies, martial arts matches, even his own clumsy punches. And when he replayed them… he was faster, sharper, better.
His muscles adapted and slowly he got better and better even without his replays.
Months later, he discovered something new: targets. He could set a cartridge to a person, and when triggered, the replay would launch toward them instead.
By then, it was clear—he wasn't just some kid with a quirk, like in MHA. He was something else. That's when the Association found him.
He wanted to change the world. Help move it into a better direction.
Only a few months after, Kouji had joined. Yuusuke still remembered their first spar. Kouji had been reckless, overconfident… and a brilliant hunter for a beginner. Somehow, that balance stuck. Over time, their rhythms locked together—strategy and instinct.
Back in the present,
"Why is this memory coming to me now," he thought.
He was glad or rather grateful—to have Kouji beside him.
The tunnel's air was thick with Idoku's poison mist. Yuusuke's vision narrowed to the glint of that thin, black blade arcing toward his chest.
"I can't move," Yuusuke thought, "Is it because of the gas?"
His thought's shifted "Kouji has grown really strong."
"Likely stronger than me," as his eyes feel heavy, "So this is my end?"
Then—
"No"
"I can't go out like that."
"KOUJI!" he shouted, the word ripping from somewhere deep.
Idoku stopped the sword.
Idoku froze mid-swing, the edge a hair from Yuusuke's ribs. His masked head tilted slightly. "...Kouji?"
Something unreadable passed in the air. Idoku stepped back, lowering the blade. His voice turned almost casual. "Interesting."
"Kouji you said?"
Yuusuke blinked, still braced for impact. "What the hell are you—"
But Idoku was already gone.
Within seconds—vanished into the tunnels, leaving only the hiss of gas fading.
Orders were orders.
Yuusuke stood there, still breathing hard. Kouji approached, scanning the darkness where Idoku had vanished. Neither spoke for a moment.
But inside Kouji, was building up unease.
"Who was that?"
Before they could recover, before Yuusuke could answer.
A Voice was screaming from Kouji's phone.
"Listen closely everyone"
"This is..."
"Humanities first Devil"