[Ding!]
[Ultimate System: Activated.]
[Initializing...]
[Detection: Host is under abnormal control status.
Abnormal control status has been lifted.]
[Detection: Special ability "Oni."
Special ability "Oni" has been retained.]
[Confirming current world.
Current world: Kimetsu no Yaiba]
A series of notification sounds rang out, and that invincible, slightly delayed voice was just so satisfying. Riku's mind snapped back to clarity, breaking free from that foggy, dazed state.
"Ultimate System?" Riku muttered, calling out to the system the moment he regained his senses. It was a bit late, sure, but it finally showed up. Clearly, this thing had some activation conditions—like a hidden spark waiting to ignite, just like Naruto's determination to become Hokage.
The name "Ultimate System" though? What's that about? Chasing the ultimate limit? Or maybe it's like, "Deep blue, show me your limits!" Riku chuckled to himself. He could already imagine Naruto shouting something like that while powering up his Rasengan. But jokes aside, this system was way better than those that only activate when you're already invincible or half-dead from old age. It's here now, so why complain? No need for a fancy bicycle when you've got a system like this!
With a thought, Riku summoned the Ultimate System's interface. A sleek, glowing panel popped up—not a physical thing, but something only he could see in his mind, like a ninja's mental scroll.
The panel had two tabs: [World] and [Personal].
Riku mentally clicked on the [World] tab, and its contents were short and easy to understand, like a mission briefing from the Hidden Leaf Village.
[World Page]
[Past Worlds: None.]
[Current World: Kimetsu no Yaiba.]
[Traversal: Function on cooldown. Charging in progress, current progress: 5%.]
"The world of Kimetsu no Yaiba, huh? Pretty popular anime, from what I've heard," Riku said, clicking his tongue. What a coincidence! He hadn't actually watched Kimetsu no Yaiba, despite it being a massive hit that nearly broke the internet.
Still, even if you haven't seen a super popular anime or played a trending game, you're bound to pick up some stuff about it. Especially the memes. Like, who hasn't heard of "Scum Boss"? Riku sure had.
And just like that, it clicked. That guy from earlier? That was Kibutsuji Muzan, the final boss of Kimetsu no Yaiba—a thousand-year-old Oni King. As the Oni King, Muzan could turn humans into oni under his control. One thought from him, and any oni he created could explode into a bloody mess. Talk about a ruthless leader, worse than any Akatsuki member!
Riku glanced at his hands. His skin was now a sickly pale, like he'd been drained of life. His nails were black and sharp, looking downright toxic. He checked out his body—muscles bulging way bigger than anything he'd ever trained for, covered in eerie black patterns that screamed "otherworldly." Add in the demonic horns, the vertical eye on his forehead, and the cracked corners of his mouth, and yeah, no doubt about it—Kibutsuji Muzan had turned him into an oni.
But thanks to the [Ultimate System], Riku had broken free from Muzan's control. He was no longer a puppet for that Oni King.
"This system showed up just in time. Saved my life right off the bat," Riku said, letting out a relieved sigh. He could feel it—no trace of that suffocating control lingered. The system had completely erased Muzan's influence, like Naruto breaking free from a genjutsu.
Good news, for sure. Working under "Scum Boss" was a death sentence waiting to happen. Better to quit and go solo, like a rogue ninja carving their own path.
"Day one of being forced into a shady organization, and the system helps me fire the boss," Riku quipped, finding humor in the chaos. It's the kind of attitude you develop when life's been a grind, and he was a pro at it.
But then it hit him. "Wait a sec. If I've broken free from his control, would Kibutsuji Muzan know?" The thought sent a jolt through him, snapping him out of his mixed emotions.
Without a second thought, Riku bolted. He had to get out of here. His current appearance—horns, freaky eye, and all—wasn't exactly street-friendly. If anyone saw him, good luck explaining that. More importantly, his brain had been screaming warnings since he came to. A deep, primal fear of sunlight. He had to find a place to hide. Getting caught in the sun meant death, no question.
"Figures. Every oni's got that 'weak to light' trait," Riku muttered as he ran, channeling a bit of Naruto's snarky commentary style. Everything was happening so fast, and the info overload was real. He needed a safe spot to sort it all out and dig into this [Ultimate System].
Under the cover of night, Riku sprinted through the streets and alleys. His body felt stronger—way stronger. He could probably take on ten or eight of his old self without breaking a sweat. Soon, he left the human settlement behind. From what he could tell, it was just a big village or small town. Why the Oni King was even here was a mystery.
To avoid Muzan, Riku didn't dare linger in the village. Instead, he headed for the dense forest outside, where a mountain loomed—a perfect hiding spot.
As he ran, a chill hit him. The air was colder now, and soft white flakes landed on his body. "Snow?" Riku held out his hand, catching a snowflake. It was cool but didn't bother him. His new oni body could handle this kind of cold, no problem.
He kept moving until he reached the foot of the mountain. There, he spotted a wooden cabin with lights on. But after glancing at his monstrous appearance, he wisely decided not to bother whoever was inside. More than that, his body was sending him hunger signals, and the enticing scent coming from the cabin—despite no cooking smoke—made it clear what was drawing him in. It was the smell of humans.
Riku forced himself to turn away and head deeper into the mountain. Soon, he found a small cave, probably some animal's old den. After checking it out and finding no creatures inside, he ignored the faint stench and settled in. It wasn't ideal, but it'd do.
Finally safe, Riku let out a breath and called up the [Ultimate System] again, this time opening the [Personal] tab.
[Personal Page]
[Name: Riku]
[Level: Lv1]
[Experience: 0/100]
[Status: Oni]
[Attributes:
Strength: 11 + 5 (Oni)
Agility: 11 + 5 (Oni)
Constitution: 11 + 5 (Oni)
Intelligence: 11
Perception: 10
Charisma: 15 - 10 (Oni)
Remaining Attribute Points: 1]
[Skills:
Oni Lv1: Transformed into an oni by the blood of the Oni King. Strength, Agility, Constitution +5, Charisma -10. Grants Blood Demon Art and Altered Constitution status.
(Altered Constitution:
1. Undying Regeneration: As long as regeneration power remains, you won't die, even if your head is smashed.
2. Death by Sunlight: Exposure to sunlight turns the body to ash, and sunlight suppresses regeneration.
3. Cannibalistic Urge: Can only consume human flesh and is drawn to its scent.
Note: Current constitution allows undying status for 32 hours.)
(Blood Demon Art: Not activated.)
Remaining Skill Points: 1
Remaining Skill Optimization Points: 1]
Looking over the [Personal] page, Riku got it. This was a classic character panel—levels, experience, six core attributes, skills, and points to assign. It felt like something straight out of a ninja scroll, with stats laid out like a shinobi's training regimen.
He quickly pieced together that the system's attributes used 10 as the human average. Most people hovered around 10, but his Strength, Agility, and Constitution were slightly above average thanks to his regular workouts. Those muscles weren't just for show! His extra point in Intelligence? Well, he'd always been a quick learner, picking things up faster than most. As for his 15 Charisma? No mystery there—he was just that good-looking, like a certain blonde ninja who could charm a crowd.
"Ultimate System, add point," Riku said, focusing on his attributes. Without hesitation, he dumped his spare point into Constitution. The undying status duration jumped from 32 to 34 hours.
"Yep, 1 point to Constitution adds 2 hours of undying time," he nodded, confirming his guess. Besides extending his survival, the boost made him feel tougher, like he could take more hits—almost like unlocking a bit of Naruto's stubborn resilience.
Next, he turned to his skills. The [Oni] skill was a double-edged kunai. The "Death by Sunlight" and "Cannibalistic Urge" drawbacks were exactly as bad as he'd felt earlier. "This is ridiculous," he groaned. "Death by sunlight, cannibalistic urges, and a 10-point Charisma hit just for a +5 to Strength, Agility, and Constitution? Did Muzan mean it when he said my oni potential was trash?"
"Ultimate System, add point!" Refusing to accept defeat, Riku threw his skill point into [Oni].
[Oni Lv2: Transformed into an oni by the blood of the Oni King. Strength, Agility, Constitution +6, Charisma -10. Grants Blood Demon Art and Altered Constitution status.]
The moment the point was added, Riku felt it—his body got stronger, faster, tougher. A +1 to all three physical stats. Not bad for a single point, though he wasn't exactly thrilled. "One skill point equals three attribute points," he mused. It wasn't amazing, but it was something. At least it boosted all three stats at once, instead of something lame like reducing the Charisma penalty from -10 to -9. If it was that stingy, he'd probably ditch upgrading this skill entirely.
Still, that -10 Charisma stung. His 15-point charm, which could've rivaled a young Kakashi's cool factor, was now down to a measly 5. Below average. For a normal person, [Oni] would tank their Charisma to 0—or worse, negative if they were already unattractive. Makes sense, though—oni eat people, fear sunlight, and look like monsters. Not exactly charming.
Riku's eyes landed on the skill optimization point. From the sound of it, this could be his saving grace. The [Oni] drawbacks were pushing his human limits, especially the cannibalistic urge. He really, really didn't want to eat people.
"Ultimate System, add point," he said, hopeful, assigning the optimization point to [Oni].
[Optimization Complete.
"Cannibalistic Urge" changed to "Shared Feast."
Shared Feast: In addition to human flesh, you can now consume oni flesh.]
"…" Riku's expression froze.
"What kind of optimization is this?!" he shouted, sounding like Naruto throwing a fit after a failed jutsu.