"Don't worry. There's a black-market dealer my sister used to trade with—he has C-rank yokai serum. It's only C-minus, but he promised me that as long as I could come up with thirty million yen, he'd sell it to me."
Now that the money to buy the serum was finally secured, Yako Ketsunari's expression visibly relaxed. She was utterly convinced that once she obtained the yokai serum, her sister would recover.
Ren Kuroda, however, frowned the moment he heard this.
Everyone knew what black-market dealers were like—people who never got out of bed unless there was profit involved, and who almost never honored favors or sentiment.A C-minus–grade yokai serum that could easily fetch fifty million yen on the market… and he was willing to sell it to Yako for thirty million?
If one ruled out the near-impossible possibility that the man was genuinely conscientious, then there were only two explanations left: either he was scamming Yako, or the serum itself had a problem.
In the eyes of a sly black-market trader, Yako was nothing more than a naïve middle-school girl. Cheating a half-grown child like her would be effortless.
"You're planning to head to the black market next, right?" Ren said after letting out a quiet sigh. "I was thinking of taking a look around Tokyo's underground market myself anyway. Let's go together."
In the end, Ren decided to see things through to the end. Bonds of family had always been the softest spot in his heart.
A girl who was willing to risk her life against unknown yokai—and had even once considered selling her own body just to save her sister—was someone he genuinely respected.
Anyone who could casually abandon their closest family… what difference was there between such a person and trash?
"Thank you, Kazuma—no, really, thank you so much!"
Yako didn't refuse his offer. Instead, she looked deeply moved, bowing repeatedly. She was sharp enough to understand exactly why Ren wanted to accompany her.
Truthfully, there was no way a normal middle-school girl carrying such a huge amount of money wouldn't be terrified of going alone into the lawless black market.
But she had no choice.
Since their parents died, her sister was her only remaining family—her only support. No matter how dangerous the black market was, she had to go.
C-rank yokai serum was simply too rare. Buying it through legitimate channels was next to impossible—and even if it weren't, she couldn't afford it. Gambling on the black market was her only remaining option.
With Ren willing to come along, Yako felt an overwhelming sense of reassurance.
They hadn't known each other for long, but the man beside her gave off a warmth she hadn't felt in years. Since her parents' death, aside from her sister, he was the first person to treat her with such kindness.
As she recalled how Ren had introduced her earlier to Yūsaburō and the others as his "little sister," she couldn't help murmuring under her breath,
"If only that were true…"
"Hm? Did you say something?" Ren asked apologetically. "Sorry, I spaced out for a second."
"N–No! I just meant… Kazuma—no, Ren—really is as gentle as an older brother."
Since "Kazuma" wasn't his real name to begin with, Ren always took a moment to react whenever she called him that.
"Hey, Ketsunari—"
"Just call me Yako," she said immediately, pouting. "I call you by your name already. If you keep using my surname, doesn't that make us sound distant?"
"…Alright. Yako." Ren hesitated for a moment, then sighed. "I should apologize first, but the name 'Satō Kazuma' was fake. Let me introduce myself properly."
He smiled faintly.
"My real name is Ren Kuroda. Nice to meet you."
The moment he said it, Yako's eyes flew open in shock. A gasp was already forming on her lips—but Ren reacted instantly, covering her mouth before any sound escaped.
"Now you get why I hide my identity, right?" he whispered. "If it got out, even going outside normally would become impossible. Since I've told you, you'll help keep it a secret, okay, Yako?"
From that point on, as they made their way toward the black market, Yako clung to Ren's arm the entire time, her face occasionally lighting up with unabashed admiration.
Now that he'd revealed his true identity, the distance between them closed even further.
Once she realized that the so-called "Hero of Tokyo" wasn't some frightening, stern figure—but instead gentle and easygoing—her behavior grew noticeably more relaxed.
"If my sister recovers and finds out I actually know someone as amazing as you, Mr. Kuroda, she'll be completely stunned," Yako said excitedly."She's a hardcore fan of yours, you know. She never cared about idols before, but her room is plastered with your posters—and full of figurines, too.
I once asked her for one of your figures, and she made me beg for a whole month!She'd never imagine that now I don't just know Ren Kuroda—I'm actually hugging the real one, not some fake figurine."
She cheerfully exposed her sister's embarrassing secrets without the slightest hesitation. After all, she was still only a middle-schooler.
Ever since learning Ren's true identity, she'd been convinced that this trip to the black market would go smoothly—and that her sister would definitely be saved.
And honestly, the fact that her sister was a diehard fan wasn't surprising at all. Ren's popularity in Tokyo was practically on par with a superstar's.
Among young people especially, many students and rookie exorcists regarded him as an absolute idol.
From Yako, Ren even learned that beyond posters and figurines, there were now novels and games modeled after him on the market. A significant portion of her sister's income had gone into buying that merchandise.
Ren's story truly was inspiring—from a fallen exorcist family's descendant clawing his way up step by step, to becoming a household-name hero.
As for Tokyo's underground black market, Ren had only ever heard rumors about it before. This was his first time actually coming here.
Contrary to his expectations, it wasn't filthy or chaotic.
The stalls were neatly organized, each vendor clearly demarcated. Crossing boundaries wasn't just rude—it was a direct provocation.
There were fewer people than on the exorcist commercial streets aboveground, but one glance was enough to tell Ren that the variety of goods here was far greater—and much cheaper.
That said, a black market was still a black market.
On the surface, there was order—but beneath it, undercurrents churned everywhere. The person calling you "brother" one second might draw a blade against you the next.
Being robbed the moment you stepped outside after a purchase was practically routine here.
Most transactions were done in cash or gold. So the instant Yako entered the market carrying a suitcase, she drew countless eyes.
A little girl in a place like this was already rare enough—and that suitcase practically screamed "fat sheep."
Feeling the hostile gazes around her, Yako instinctively moved even closer to Ren.
She'd been here once before—but back then, she hadn't encountered anything like this. She'd foolishly thought the black market wasn't as dangerous as rumored.
Now she understood.
It wasn't that the black market had been safe before—it was that she'd been too poor to be worth targeting.
The reason the black market could exist at all was because powerful figures backed it. No one dared cause trouble openly inside—but once you left, all bets were off.
With Yako visibly nervous and Ren openly curious, they passed through several zones before finally reaching the stall run by the dealer her sister knew.
The man was middle-aged, wearing a skull-printed tank top, a cigarette dangling from his lips. He looked like a washed-up thug straight out of the gutter.
Yet despite his slovenly appearance, the size of his stall made one thing clear—this man had clout in the black market.
Here, territory was earned through blood and brutality. Only the ruthless survived.
"Uncle Chihyō," Yako said, setting the suitcase down in front of the stall."I brought the money, just like I promised. Please sell me the C-minus yokai serum you mentioned before. My sister's still waiting for it to save her life."
"Oh? It's you, huh?"
Chihyō stared at the suitcase full of cash, his face registering genuine surprise.
"I didn't think you'd actually scrape together thirty million yen. Looks like you found yourself a sugar daddy." His eyes slid toward Ren."So what, then? How many times did you sleep with this pretty boy to earn it?"
He licked his lips as his gaze wandered over Yako's still-developing body, lewd and undisguised.
He'd never had a middle-school girl quite like her before.
He'd assumed that to save her sister, she'd eventually have no choice but to come crawling back to him. But someone else had beaten him to it.
"Ren—n-no, Kazuma isn't like that!" Yako snapped, her face flushing with anger."I've brought the money as agreed. Please take out the C-minus yokai serum.
We had a deal. You said that if I gathered the money within a week, you'd sell it to me.Even you wouldn't dare break the black market's rules, would you, Mr. Chihyō?"