Wasn’t it said the Luminous Twilight Earl was a solitary, lofty vampire with no blood relatives or subordinates?
Himeragi Yukina felt that rumors couldn’t be trusted lightly.
She didn’t know if the Fourth Progenitor had friends, but at the very least, he had family.
However, Himeragi Yukina was absolutely certain of one thing: Komachi was a completely ordinary human.
Definitely not a vampire or anything else…
The situation was a bit complicated, but Yukina had already sensed Hachiman Hikigaya’s hostility and threat.
That heavy, oppressive feeling was almost becoming tangible—like the pressure before a thunderstorm, when the air itself seems to hold its breath.
This is bad.
Because she was coming to a friend’s house to visit, she hadn’t brought the Yukihira with her.
After all, she wasn’t a school idol pursuing a music dream—Yukina didn’t always carry a big box around like some kind of wandering minstrel.
Facing the rumored strongest vampire, if she had the Yukihira, perhaps she could still put up a fight.
But now?
What could a novice Sword Shaman, empty-handed, possibly do?
Die, her training supplied helpfully.
Probably die.
“Stupid big brother! Don’t stare so intently at your little sister’s classmate!”
Just as Yukina was breaking out in a cold sweat, that harmless-looking classmate delivered a karate chop to the Fourth Progenitor’s head.
Though it looked completely effortless—almost playful—it still scared Himeragi Yukina into cardiac arrest.
How dare she?!
That was the Fourth Progenitor!
The incarnation of a natural disaster!
Yet, unexpectedly, that oppressive feeling vanished instantly.
All that remained before her was a harmless-looking unfamiliar youth with dead-fish eyes, who lightly brushed off his sister’s hand and continued drinking his coffee as if nothing had happened.
As if nothing had happened.
He just…
let her do that.
“Even though Komachi knows Yukina-chan is super cute, big brother, could you tone it down a bit? People will think you’re a creepy teenager.”
“You mean creepy old man, right? I don’t recall there being a term like ‘creepy teenager’ in my vocabulary.”
“Don’t worry! I’ll explain to Yukina that big brother is a good person.” Komachi smiled brightly.
“Big brother wants to leave a good impression on Yukina-chan too, right?”
“I don’t really care about that. In fact, you don’t need to explain anything.”
“Is that so? That fits big brother’s way of thinking too.” Komachi nodded sagely.
“Besides, making a move on a middle school student—while not illegal anymore—is still somewhat immoral.”
“Who would make a move?”
Komachi nodded again, as if agreeing with Hachiman’s words.
“The only girl who would like big brother the way he is now is Komachi!”
“Komachi’s line just now scored pretty high.”
Amazing.
This middle school student had completely suppressed the Fourth Progenitor.
Could she be even stronger than the Fourth Progenitor?
No, Yukina realized.
She’s just…
his sister.
That was somehow more terrifying.
“Yukina-chan, please watch TV on the sofa for now. Komachi will go make you some coffee. Big brother, come help too.”
“Mm. Okay.”
This was the Hikigaya family’s unique ability to sense subtext—the unspoken language of siblings who had spent years learning to read between each other’s lines.
Clearly, Komachi’s subtext was that she had something to say privately.
“Confess honestly, big brother.” Komachi’s voice dropped to a whisper once they were in the kitchen.
“Do you know Yukina-chan?”
“Was it that obvious?”
“Well, your expressions were practically screaming ‘How could it be him (her)?’ on your foreheads. Both of you.”
After all, the shock they both felt upon meeting was impossible to hide.
This Yukina-chan was indeed a beautiful girl—one could fall in love with her at first sight, probably.
But Hachiman believed he was definitely not the type of handsome guy a girl would fall for at first sight.
That kind of thing only happened in anime.
And this was reality—where he had dead-fish eyes and a personality that repelled normal human contact.
“How to put it…” Hachiman hesitated.
“You might not believe it if I told you. How about you tell me first—how well do you know her?”
“We’re good friends!” Komachi beamed.
“Yukina just transferred yesterday, and today Komachi and Yukina became super close friends! How about that? Komachi is super amazing, right?”
“Wait.” Hachiman’s brain skidded to a halt.
“You mean this girl just transferred yesterday?”
“Yeah, that’s right! Yukina-chan’s surname is very special—Himeragi. It feels like a winter princess, doesn’t it?”
Himeragi.
Hachiman’s previous speculation was completely overturned.
If this girl transferred yesterday, fell in love with Komachi at first sight, then found out about her brother’s information and started stalking him…
No matter how he thought about it, that was impossible.
The timeline didn’t work.
The logic didn’t hold.
And the attributes and labels he’d attached were far too many—even for his overactive imagination.
Then why was she stalking him?
Hachiman already had some answers in his heart.
Teacher Shizuka Hiratsuka’s hints.
The non-human members in the Service Club.
The way Yukino had looked at him—not with surprise, but with recognition.
All of it made Hachiman realize one thing: the secret he thought he’d kept so well might have already been known by others.
After eliminating all other possibilities, the only conclusion left was that his little sister’s classmate wasn’t here for Hachiman Hikigaya.
She was here for the vampire.
Or perhaps…
she might even be here for the Fourth Progenitor.
“Komachi.” Hachiman set down his coffee.
His voice was quiet now—no irony, no deflection.
“I’m going to tell you something now. Don’t be scared, okay?”
Komachi tilted her head.
“Rest assured! Komachi is a professional. There is nothing that will make me afraid.”
“I am a vampire.”
“Pfft.”
“You just laughed, didn’t you?”
“No, no. Komachi is a professional. I wouldn’t laugh.”
“I’m not joking, Komachi.” Hachiman’s voice didn’t waver.
“Ever since I came back from the summer vacation trip, I have indeed become a vampire.”
Komachi stared at him.
Then her expression shifted—just slightly—from amusement to something more uncertain.
“Are you serious?” she asked slowly.
“Big brother, you’re already past the age for chuunibyou.”
Hikigaya didn’t offer any further explanation.
He simply opened his scarlet pupils slowly—letting the crimson bleed across his irises like dawn spilling over a dark horizon.
His fangs gradually grew, extending past his lips, becoming sharper.
Real.
Not a costume.
Not an act.
Not a phase.
Komachi’s eyes widened.
Then Komachi whispered, “…Huh.”
“That’s super cool!”
“Huh?”
“Big Brother, why don’t you just stay like that? You look super cool. If you looked like this all the time, you’d be really popular!”
…What?
“No—aren’t you surprised at all?”
Hikigaya couldn’t understand.
His brother—whom she saw every day, who shared meals with her, who bickered with her over the remote control—had suddenly turned into a vampire.
Why did Komachi seem to have no trace of shock or fear?
Where is the screaming?
Where is the running away?
Where is the existential crisis?
“It’s not like there were absolutely no signs,” Komachi said, tilting her head as if recalling something from a detective novel.
“You weren’t exactly hardworking before, Big Brother, but you weren’t this ridiculously lazy either.”
Fair point.
“You seem like you don’t want to go out at all. You get really lethargic as soon as you’re in the sun, but you seem exceptionally energetic at night. You don’t even sleep when staying up very late.”
“Waaah—my cute little sister is actually so concerned about me. I’m so moved. Hachiman just scored very high points!”
“No, not at all.” Hikitani Komachi expressed her rejection with the clinical precision of a seasoned professional.
“It’s actually a bit disgusting.”
Even with such a handsome face—and he was being generous with that assessment—this kind of emotional display revealed a subtle sense of disgust that Komachi did not bother to hide.
Brutal.
But fair.
“Then, does Big Brother have to drink blood every day now?” Komachi’s eyes narrowed.
“Masaka… could it be that you go out hunting for women every night?”
“No, absolutely not.” Hachiman raised his hands in defense.
“Although I do prefer food with blood a bit more—steak, rare, that sort of thing—ordinary food can still keep me full. Don’t make your brother sound like a criminal.”
“Then, if you didn’t drink Yukina’s blood…” Komachi’s gaze turned analytical.
“Why did you two make that expression when you looked at each other?”
Hachiman sighed.
“Up until now, I haven’t drunk any blood. As for that transfer student you mentioned…” He paused, weighing his words.
“You might not believe this, but she stalked me yesterday. It took a lot of effort to shake her off.”
Hikitani Komachi didn’t doubt it.
That was the surprising part.
After learning about the bizarre fact that her brother had turned into a vampire—after seeing the crimson eyes and the sharp fangs with her own eyes—she simply…
accepted it.
Filed it away.
Moved on.
Is this what they call unconditional sibling love?
Hachiman wondered.
Or has Komachi always been this terrifyingly adaptable?
“How about this.” Komachi placed her hands on her hips with the authority of a general issuing orders.
“Big Brother, go back to your room first. Leave the intelligence gathering to Komachi!”
Intelligence gathering.
She said it like she was a spy in a cold war movie.
Like this was just another Tuesday.
Hachiman stared at his little sister for a long moment.
Then, despite everything—despite the vampire blood coursing through his veins, despite the familiar beasts sleeping in his soul, despite the dead-fish eyes and the cynical worldview—he felt something warm settle in his chest.
Komachi is the best little sister in the world.
“…Don’t do anything dangerous,” he said quietly.
“Komachi is a professional!” She gave him a thumbs up and a wink.
“Now go. Shoo. Vampires aren’t allowed in the kitchen during intelligence operations.”
Hachiman shook his head—but he was almost smiling as he turned and walked back toward his room.
Almost.