Half a year ago, Mika Takana applied for a part-time job at Himawari Mart because her children had finally started elementary school, giving her some free time. The store manager was a kind-looking woman who seemed just a little older than 38-year-old Mika—which was also a big reason she chose this supermarket.

That day, she learned how to handle the register, clean, and stock shelves. The next day, she was handed a key with a green ribbon attached. It was the key to Warehouse No. 4.

“There’s a door on the cliff out back, and I’d like you to bring some items out from inside. You know the old sales floor from two generations ago? These are the products to display there. Everything’s piled up haphazardly, but just pick whatever you like, Mika-chan, and bring it to the store.”

“Just between us… that place has a black demon. Are you okay, Mika? Take some insecticide and cleaning supplies with you—and if you could clean up while you’re at it, that’d be great.” The manager said it so cheerfully. Mika, having raised two kids, casually replied, “A black demon? No big deal.” And so, she entered Warehouse No. 4 for the first time.

Inside, the cave-like space was far more spacious than she expected, stretching so deep she couldn’t see the end. Random items were carelessly placed in hollows along the walls—tiny child-sized armor, wooden boxes with strange patterns, a rusted dagger, accessories that were awkwardly sized (too short for a necklace, too long for a bracelet), and ancient coins inside a jar, so old their era was impossible to guess.

“Who would even buy this stuff?” Mika muttered.

As if in response, a high-pitched “Kee—!” echoed from the depths.

“Eek!”

Panicking, she grabbed the insecticide and looked up—only to see three demonic creatures, about 30 centimeters tall, with bat-like black wings, swooping down at her.

“KYAAAA!”

She shut her eyes and sprayed the insecticide wildly in their direction.

She must’ve held down the spray button for a full minute. Eventually, the screeching “GYAA-GYAA!” sounds faded, and Mika cautiously opened her eyes.

On the ground lay three black lumps.

No matter how she looked at them, they were not cockroaches.

Glancing at the nearby wall, she noticed a large hole, with a red ribbon tied to a protruding rock above it.

“Oh, right—she did say to throw the trash into the red one.”

Grabbing the cleaning supplies she’d tossed aside, Mika threw the black lumps into the hole.

“So the ‘black demon’ is real after all. That was a shock.”

With that, she quickly pushed the thought of the black demon out of her mind and went back to selecting products—though she couldn’t decide whether to call them antiques or just junk.

A 38-year-old mother of two wasn’t about to be rattled by something like this.