The first question Kaito had was practical.
He was four. His legs were short, his arms were useless, and the most physically demanding thing he had done since waking up in this body was climb out of a bed that was two feet off the ground. If his quirk required him to find a dead body and climb inside it, he needed to understand what that actually looked like at this size.
"When I take over a body," he said, sitting cross-legged on his bedroom floor after breakfast, speaking quietly so his mom would not hear him apparently talking to himself, "does it keep deteriorating? Like, is it rotting while I am in it?"
"No. As long as you are possessing it, the body holds. The decay stops."
"And if I leave?"
"It resumes."
"So the clock is always running when I step out."
"Yes. Which is why freshness matters. The sooner you possess a body after death, the better the condition it will be in. A body left for three days before you find it is not unusable, but it is not ideal either."
"What happens if I die while I am inside one?"
"You are ejected back into your own body."
"Just like that?"
"Just like that. Your main body wakes up wherever you left it."
"So technically, as long as I am inside a shell, I cannot actually die."
"Correct. As long as your main body remains alive and intact, you cannot be permanently killed while possessing another. You would simply be sent home."
"So I am immortal as long as I stay in a shell."
"That is a reasonable way to describe it, yes."
He let that sit for a moment. The kid who used to have anxiety attacks in cars because he was scared of dying could not be permanently killed. He was not sure if that was funny or deeply unsettling. Probably both.
* * *
"Okay," he said. "How am I supposed to actually practice this at four years old? I cannot exactly walk up to a hospital and start asking questions."
"Possess a dead animal. A cat, a bird, something small. Japan has strays. You will find something."
Kaito stared at the ceiling.
"I am going to be a four-year-old possessing a dead cat."
"To start, yes."
"Great. Very heroic."
"You asked."
He moved on. "What happens if I possess something completely different? Like four legs. Or something with three eyes. Does my brain just break trying to figure that out?"
"No. Control is instant. The moment you enter a body, you understand it. Two legs, four legs, no legs. You simply know how it moves."
"What about the quirk?"
"The quirk is more complex. You can use it, but only up to the level the previous owner had mastered. Muscle memory, technique, control. Whatever they built in life, that is your ceiling inside that shell."
"But I get a boost."
"Yes. Your soul is stronger than theirs was. So the power you access will be greater, roughly one and a half times what they were capable of at their peak. Though I want to be honest with you about something."
The HUD shifted slightly, like Gloom was choosing words carefully.
"Do not think of it as becoming the strongest person in the world. That only applies if the body you possess already had that potential. A mid-tier hero with a mid-tier quirk times one and a half is still just a better mid-tier hero."
"But if I found someone who was actually at that level?"
"Then yes. The ceiling can be very high. But that is not your concern right now."
Fair enough. "Does the quirk change visually?"
"Sometimes. Fire might burn a different color. Water might shift into something adjacent. Or it looks exactly the same. There is no consistent rule. You will only know when it happens."
"What about how I look when I am in someone else's body?"
"Your appearance shifts. Different hair, different eyes, sometimes different features entirely. Most people will simply see a person."
A pause.
"However. If someone knew the original owner well, they may notice something is off. They will not see a stranger. They will see someone they recognize but slightly wrong. Like the person is wearing their own face as a costume."
That landed in a strange place in his chest.
"So I could walk up to someone's family in their dead kid's body and they might not even know."
"Yes."
"But they might."
"Yes."
He did not say anything for a while after that.
* * *
"Can I see my stats?"
"Yes. But I want you to understand what you are looking at first."
The HUD shifted and something like a soft vibration moved through the space just behind his eyes.
"Everything in this body is currently a five. That is the floor. The baseline every living body needs to function. If you possessed an adult right now you would see numbers in the hundreds. But those numbers are not absolute. They are relative to you."
"Like a personal scale."
"Exactly. And here is what most people would miss. If your main body is weak, those numbers lie to you. Say you possess a shell and it reads one hundred and fifty in strength. You assume that is powerful. But one hundred and fifty relative to a frail, untrained anchor is not what one hundred and fifty looks like for someone who has been training for years. The shell is not weaker. Your reference point is. You would step out of that shell and back into a body that cannot cash the check."
That one landed differently. He had already been thinking of the shells as the real power, the main body as just the thing he came home to. Gloom was telling him that was exactly the wrong way to think about it.
"So I cannot let the shells do all the work."
"That is the point. Your main body is the lens everything gets measured through. Keep it weak and you will always be miscalibrated. You might think you understand a shell's power and be completely wrong about what you are actually capable of."
"Also," Gloom added, "you are in Japan. Possessing bodies may be complicated here. Not impossible. But the government may watch you. The public may have opinions."
"You think the government would actually work with me on it?"
"I think if you are saving people and have proven you are not killing anyone for their bodies, yes. Governments are pragmatic when it is useful to them. The public takes longer. But trust is built the same way everywhere."
He thought about that. A hero who walked around in dead people. He could already picture the news coverage.
"Show me the HUD."
* * *
The display opened across his vision, clean and sharp against the morning light of the bedroom.
╔══════════════════════════════════════╗
║ 🖤 GLOOM SYSTEM v1.0 🖤 ║
╠══════════════════════════════════════╣
║ HOST : KAITO MURA ║
║ AGE : 4 ║
║ STATUS : ✅ ACTIVE ║
║ QUIRK : 🐚 SHELL ║
║ SHELLS : 0 ACTIVE | 0 STORED ║
╠══════════════════════════════════════╣
║ 📊 MAIN BODY STATS (BASE = 5) ║
╠══════════════════════════════════════╣
║ 💪 STR 5/5 [█░░░░░░░░░] ║
║ ⚡ SPD 5/5 [█░░░░░░░░░] ║
║ 🛡️ END 5/5 [█░░░░░░░░░] ║
║ 🌀 AGI 5/5 [█░░░░░░░░░] ║
║ 🧠 INT 5/5 [██░░░░░░░░] ║
║ 🎯 QCT 5/5 [█░░░░░░░░░] ║
║ 👻 SOL 5/5 [█████░░░░░] ║
╠══════════════════════════════════════╣
║ 📝 NOTES ║
║ > Stats = main body baseline ║
║ > Shells show separate overlay ║
║ > Shell stats = 1.5x owner base ║
║ > Weak body = skewed shell reads ⚠️ ║
║ > Main body VULNERABLE in shell ☠️ ║
║ > SOL cannot be trained ║
╚══════════════════════════════════════╝
He stared at it for a long moment.
"Soul Strength is the only one that actually looks like something."
"It is the only stat that cannot be trained. It is simply what you are. And it is, for the record, unusually high."
"Good to know something works."
He closed the HUD. Outside the bedroom window the neighborhood was waking up. Traffic, voices, the distant sound of someone sweeping a front step. Normal. Quiet. A city that had no idea what was living inside one of its four-year-olds.
He had a long way to go. He knew that. But for the first time since he woke up in this body, the fear that had chased Joshua Park through sixteen years of his first life was nowhere to be found.
Kaito Mura had died once already.
He was not planning on doing it again.