Laboratory, the site of the black market.

At this hour, only Agnes Tachyon remained inside. She sat behind the counter, carefully tallying the types and numbers of potions sold tonight, writing the data into her notebook.

For a researcher, data logging was indispensable—the cornerstone of all study. Even something as simple as recording inventory could not be done sloppily.

Tonight's sale had been a resounding success. In just half an hour, she'd earned enough funds to sustain several months of research.

The Uma who came all had the same purpose: to buy stamina potions and pelvic durability enhancers. They didn't spare a glance at anything else. So the whole process was brisk—buy what they needed, leave immediately. After all, their Trainers, still smelling so enticing, were waiting in their rooms.

The only oddity had been that strange black-clad figure.

Had she not put on her little invention before opening the black market, she never would have noticed the shady aura hanging at the end of the line. She'd stared for quite a while before realizing someone was even there.

At first, she didn't know what he was plotting. But after she casually warned everyone not to steal—and that black figure bolted away in a panic—well, that more or less confirmed it. He'd come to steal potions.

Really now. If you wanted potions, was stealing necessary?

Spend a few days as her lab rat—as compensation... no, as payment—and she could have given him a few stamina potions.

"Aahhh—" Tachyon yawned, weary. She planned to finish tidying the numbers, then close up tonight's market and go sleep.

But just as she slipped the night's profits into her bag, something flickered at the corner of her eye—at the door.

When she turned to look, there was nothing. Just a vague, indistinct black haze.

"?" Tachyon tilted her head. Unsure what was emanating that aura, she narrowed her eyes, focusing.

"?" Mizuno, too, was puzzled by her reaction.

Didn't Tachyon just a while ago see through him as if she had x-ray vision, even read his mind, calling him out despite his low presence? Why was she now acting like she couldn't see him at all?

Could it be...

Tachyon's ability wasn't true x-ray vision or mind-reading?

"Let's test this." To confirm, Mizuno somersaulted on the spot.

"Grass, walk, ignore!"

?????

Tachyon didn't react.

"Kindness! All evil! Will be brought to justice!"

Mizuno went into a full set of military boxing drills. Still no reaction.

For ten whole seconds, Mizuno struck pose after pose, every single one ridiculous enough that any sane person would have heckled him instantly.

But Tachyon's expression remained unchanged, like an old granny squinting at a newspaper—straining to read, but not really noticing his antics at all.

Only after several long seconds did she finally catch sight of him. Her whole body jolted, ears and tail snapping upright in alarm.

"You again? Trying to steal from me again?" Tachyon exclaimed, brows knitting.

Hadn't this guy just run off? Why was he back?

And what was more—he still radiated that aura of malice. Weaker than before, but still there.

"Oh?"

Her words confirmed Mizuno's hunch.

The time it took Tachyon to notice him at the doorway was about the same as when any normal person would hear him call out and then, after focusing, finally spot him.

Which meant: she didn't actually see him. She only sensed that someone was there. She had to stare for a while to pick him out, just like everyone else.

And earlier—he'd already borrowed money, planned to make a proper purchase—yet she still accused him of "trying to steal again."

So her "mind-reading" was fake too. She only knew that Mizuno had some harmful intent toward her.

In that case, Mizuno no longer needed to be afraid.

"That outfit of yours... lowers your presence?" Tachyon suddenly asked.

While Mizuno analyzed her, she was analyzing him. Why could he vanish?

Full-body concealment, only visible after staring...

Her conclusion: his clothes lowered his presence.

"Guess..." Mizuno refused to answer.

Ever since he'd been ambushed once by two senior Trainers, Mizuno had vowed never again to reveal his outfit's functions. Better to keep others from scheming after it.

And the best reply was always "Guess."

Neither confirming nor denying. No matter what the other said, give nothing away. Let them grope in uncertainty.

On top of that, Mizuno threw in a diversion.

"Then you can see the... malice aura around me, right?" he asked back.

"That's right."

Tachyon saw through his topic shift, but unlike Mizuno, she had no qualms about exposing the truth of her ability. In fact, she wanted to.

She reached to her nose, pinched, and removed—

A pair of glasses?

She'd been wearing them all night—clear lenses. But in the dim room, no one had noticed.

Placing them on the table, she introduced them in the same cheerful tone she used to sell potions:

"This is my invention, the [Intent Glasses]. They judge a person's general intent and emotions by the color and shape of their aura."

"White means goodwill. Pink means love. Black means malice..."

"Red is anger, blue is anxiety, yellow is happiness..."

"Heart-shaped is affection. Triangle is neutral. An X means dislike..."

"It can even display the degree of intent in numbers."

"All the other customers tonight were white triangles, their numbers high. Since they could get useful potions here, they held goodwill toward me."

"But you..."

"You've been a black triangle from the start. Your numbers are lower now than when I first spotted you ten minutes ago, but you still carry malice toward me."

Tachyon tapped the table. Her smile remained, but her tone made clear she resented Mizuno's attitude.

In other words—

What? Still planning to steal from me?

"Ah..." Mizuno scratched his head awkwardly.

He wasn't going to steal. But he was planning to buy a potion, then go straight to President Rudolf and report Tachyon for running a black market...

That tiny bit of malice was detectable too?

"I just thought... black hearts don't mean, like..."

Tachyon's lips curled.

"Yandere~"