Prologue

“Come to think of it, I just sensed a presence here that was even more captivating than my Onii-chan’s… Youli is truly cunning; she wouldn’t let me use my abilities to travel quickly~ Now… sigh… did I miss it?”

Hearing my sister’s words, I was momentarily stunned. Indeed, as I observed, my sister had once again demonized. However, this time, the feeling she gave me was somewhat strange. While her eyes had completely transformed into the narrow, vertical slits of a demon, compared to when I had last seen her, her killing intent toward me had noticeably softened.

I could still sense the demon’s inherent obsession, but… her target of hatred seemed to have shifted. If before, I had been a “marked obsession” that needed to be eradicated at all costs, now, my sister’s gaze upon me was more like… she could eliminate me, but also wouldn’t mind leaving me to my own devices.

****

I suddenly recalled what the “human counterpart of Ye Qi” had told me before she left. My sister had explained that this bizarre body-swapping situation was a plan to save herself. To divert her demon form’s target of hatred, she had orchestrated my body swap with the Valkyrie. Compared to me, the consciousness now in the Valkyrie’s body, it seemed the Valkyrie occupying my original body was the true source of Little Qi’s turmoil. After all, a demon’s obsession only needed to be fulfilled once, and my sister seemed eager to exploit this loophole.

****

Only after realizing that her hatred seemed to have completely shifted did I muster the courage to speak with my sister. The sister from before had fully entered the realm of a demon god; if an ordinary human without abilities were to meet Ye Qi’s crimson gaze, they would likely descend into madness within three seconds.

“…Little Qi.”

Carefully observing that she showed no intent to attack, I slowly approached her.

“The Valkyrie has already left. She departed about three minutes ago.”

“Left?!”

Upon hearing my words, my sister’s face fell into a look of profound disappointment. Her already fair face instantly grew even paler, almost ghost-like—it was the kind of expression one would have after discovering they’d won a hundred million in the lottery, only to realize the ticket was from a previous draw. “…Three minutes ago? I shouldn’t have agreed to Youli’s request not to use my abilities.”

Lowering her head, her features obscured by her pale bangs, my sister mumbled in a tone on the verge of tears. Then, she abruptly lifted her head. This time, her demonized vertical pupils had reverted to their previous pinkish, crystalline red hue, and baring her fangs, she angrily chastised me.

“Why?! Huh? Onii-chan, why didn’t you make her stay? Wasn’t she trying to get her body back? …And your bodies haven’t even swapped back, have they?! Why did she leave without waiting for me?! How utterly inconsiderate?!”

My sister was clearly furious.

“Argh! Damn it!” With one hand, she tugged at the seemingly immovable collar around her neck while stomping her feet furiously on the ground.

****

I understood my sister’s anger. Three minutes for a demon was roughly equivalent to three days for a human. Their terrifying mobility allowed demons to reach distant locations in an extremely short amount of time. While my sister could also achieve this, unfortunately, her demonized form didn’t seem to possess the power of tracking. Moreover, Little Qi didn’t have a keen sense of smell or an internal radar. So, even if she started pursuing now, she would only get lost in the air like a headless fly, with virtually no chance of catching the Valkyrie.

“Little Qi, calm down and listen to me first… That Valkyrie seems quite fond of my body. She appears particularly fixated on a body ‘without fat deposits’… it’s as if she has no intention of returning…”

‘And she was likely scared away by you’—I didn’t dare say that last part to my sister.

****

“Huh? What kind of joke is that woman playing?! What’s wrong with cellulite?! And she scorns her own body but prefers yours? Huh? She’s just showing off, the scoundrel!!”

After hearing this, I could see the fury on Ye Qi’s face. Having gradually come to terms with her inherent female identity, she was growing increasingly conscious of her boyish physique—the very type Youli seemed to prefer as well.

“Uh.”

I lowered my head in embarrassment, glancing down at the prominent curve beneath my school uniform.

It was bound tightly by a man’s shirt underneath, yet it still obstructed my view of my own feet.

The Valkyrie’s physical development seemed to be born entirely from the fantasies of men on the battlefield, an almost obsessive endowment.

“I think it’s probably bad for vision… and the center of gravity shifts slightly… I also feel a bit uncomfortable…”

“…Onii-chan.”

My sister’s voice suddenly became unsettlingly gentle. After I finished my muttered self-assessment, in the blink of an eye, Little Qi’s large eyes suddenly appeared right before me.

“Yikes!!!”

Up close, her large, round, crimson eyes resembled glowing orbs. I yelped in alarm—she had been a whole room away just moments ago?! Then, a sharp, stinging pain shot through my chest; Little Qi’s small hands had seized a rather sensitive area.

“Oh, is that right? The center of gravity shifts, does it? Well then, let’s make it swell up and shift even more! Let me tell you, Onii-chan, my breast enhancement techniques are quite highly acclaimed… Hehehehehehehe…”

“Stop! No! Little Qi! You!! That’s… that’s my…!???!”

****

After her outburst, Ye Qi turned her back to me. Although her face still held a fierce scowl, the expression she showed was no longer one of wanting to kill me, as it had been before. At the very least, I could even hear a hint of her usual affectionate tone returning. Watching Little Qi still stomping her feet in a fit of pique, I smiled.

Compared to the chest that would likely remain swollen for days from her ministrations… truly, my sister’s smile was far more important.

So thought Ye Sakaki, who absolutely did not consider himself a siscon.

****

Finally, after our playful antics concluded, my expression suddenly grew serious. While my own immediate problems were less pressing, there were still other issues to consider. For instance… a certain Tenshouin Youli.

I didn’t know what had possessed Tenshouin. In the past, I had always stubbornly believed Tenshouin to be a gentle, generous, well-mannered, and charming girl, but… today’s Tenshouin had utterly shattered my understanding of her. She had bribed an ability user through unknown means, and… Tenshouin, who almost never uttered a single curse word, actually dared to refer to a teacher as a “son of a b*tch.” When I heard that, I even thought Tenshouin had been possessed by a demon—though I wanted to believe Youli was merely possessed when she acted that way, Naiya, however, was right beside Youli. I knew that no matter how unscrupulous my club president might be, they wouldn’t possibly accept a demon’s commission… would they?