Akaza was one of the earlier demons under Muzan's command to truly stand out. After becoming a demon, aside from following orders to search for the so called Blue Spider Lily, he had remained obsessively devoted to one thing: crossing fists with the strong, sharpening himself through combat until he grew stronger and stronger.
That was what Rinko knew, at least. He'd heard it all from Muzan.
It was said that even Akaza's transformation had been an accident. In a place where there should have been no demons, the death rate rose to something unnatural, so Muzan went to investigate. When he returned, Rinko had gained a new bedtime story. Even though he didn't need one, Muzan still told it slowly, as if he had all the time in the world.
Muzan spoke highly of Akaza. Loyal. Practical. A doer. Not long after becoming a demon, he'd already become a Lower Rank, and ever since, he had trained while challenging upward, trying to climb higher.
Rinko had heard plenty, but in truth, he and Akaza had never met. It was only because Muzan almost never praised other demons that Rinko ended up slightly more curious about Akaza than he ought to be.
Curious did not mean he wanted to meet him.
Muzan, however, had his own interpretation.
The child was interested. The child wanted to make a new friend.
"Akaza. This is Rinko. I'm leaving him with you for now. Keep him at your side."
Akaza had heard the name before, from other demons.
They said that beside Lord Muzan there was an unremarkable little child, so small you couldn't tell whether he was a human child or a demon. A tiny thing, weak as paper. Some of them had even joked, cruelly, that he might be a reserve ration.
Akaza wasn't interested in rumors. He wasn't interested in eating children, either. And since Muzan had never brought that so called child when visiting him, Akaza had assumed they would never cross paths.
Clearly, he hadn't prepared enough.
Not only were they meeting, he was being told to keep this "reserve ration" at his side.
"Do you need me to do anything, Lord Muzan?"
He asked naturally, already thinking: if there's some task attached, finish it quickly, and then send the kid back.
"No. If you can teach him something, teach him. Anything is fine. If he can't learn, don't force it. Rinko has his own use. You just need to keep an eye on him and make sure he doesn't stumble into Demon Slayers and lose his head."
So it was a troublesome errand after all.
But Akaza had no room to refuse. He knelt on one knee, lowered his gaze to the ground, and accepted in silence.
Only after the pressure lifted did he raise his head, ready to properly look at the "reserve ration" who had lived only in rumor.
What stared back at him was a child.
Bare feet. A strip of thin calf exposed. Loose shorts. An even looser outer robe, clearly put on by someone who didn't care about fit, absurdly oversized. Even tucked into the waistband, the hem still hung long. The sleeves were so long they swallowed his arms completely.
Akaza would have believed it was one of Muzan's own garments.
Above that was a pale face and a pair of gray blue eyes, unblinking, calm to the point of blankness. No obvious emotion at all. Only the vertical pupils proved what he was.
He looked like a slightly slow kid.
And ridiculously weak, to the point that it was hard to tell if he even truly existed.
"I'm Rinko. My name is Rinko. It's our first meeting. Please take care of me."
When he opened his mouth, small demon fangs showed. Children were hard to judge by appearance alone, but once he spoke, Akaza could tell he was a boy.
Slow, maybe, but polite.
"Akaza."
Compared to human children who would scream and cry the instant they saw him, Rinko was the sort Akaza could at least tolerate.
That was the good news.
Akaza had nothing else to cling to, so he took it.
"Since Lord Muzan handed you to me… then we can only get along properly."
Akaza swept his eyes over the skinny little thing again. Forget Demon Slayers. He looked like even a random demon passing by could crush his skull with two fingers.
Taking care of him was, nine times out of ten, not going to be easy work.
Watch this kid's head. Don't let Demon Slayers cut it off.
A little creature with no ability to protect himself would be the first target to be beheaded.
"You don't have to take his words to heart."
Akaza was walking ahead, still thinking, when Rinko spoke without warning. The voice was right beside him. And the boy was right beside him, too.
"Without warning" wasn't exaggeration. It was literal.
In Akaza's senses, the boy had been two steps behind. But in the instant before speaking, he vanished from Akaza's perception. In the next breath, he was simply at Akaza's side.
Before showing any reaction, Akaza countered.
"I mean, about not letting you run into Demon Slayers. I can watch myself. You can move according to your usual habits. It's fine."
Akaza's face twisted.
He even forgot about the strange vanishing act for a moment.
What kind of nonsense was this kid saying? Did he understand how easily his head would be singled out? Did he understand how weak he was?
Protect himself? And telling Akaza not to listen to Lord Muzan?
How many heads did the two of them have to lose?
"Don't worry, I…"
Akaza lifted a hand and cut off the explanation, raising one finger.
"First. Don't call me 'sir' like that. Second, kid, how many heads do you have for Demon Slayers to chop off?"
He tapped two fingers against the boy's fluffy head. Not gently. The force made Rinko's head tip back.
"With you like this, forget Demon Slayers. Even demons could tear you into three pieces. Get a clear sense of where you stand."
Akaza sighed, straightened, and waved him onward, continuing down the path.
If someone didn't believe you, no amount of explaining would make them believe you.
Rinko understood that well.
So he didn't expect to persuade Akaza in a single attempt.
He accepted the arrangements from Akaza, who clearly saw himself as an elder obliged to "supervise" him, though it was written as management and read as caretaking. At the same time, Rinko quietly began thinking about his next plan.
Akaza's routine was terrifyingly regular.
The moment night fell, he ran everywhere. Training. Searching for flowers. Fighting demons. Sometimes fighting humans.
The last time Rinko had been yanked off the ground the moment the sun set was back when he trained under Kokushibo.
And that had been a very, very long time ago.
Rinko didn't really understand why Muzan had suddenly arranged for him to stay by Akaza's side.
Their temperaments and ways of living were worlds apart.
Where Rinko preferred to sit quietly, Akaza preferred to find something and fight it all night.
Rinko had no doubt that if he suggested sitting together to watch the stars, Akaza would punch him so hard he'd only be seeing stars.
An endlessly energetic man in his prime, and a gentler, more inward little boy.
How could they possibly agree on anything?
But it was Muzan's order.
Whether it was Akaza or Rinko, all they could do was accept it.