My Ex-Girlfriend’s Sister Ran Away to My Room, and We Can’t Stop Making Mistakes.

Femme Fatale.

“Whoa. You look even more like your soul’s been sucked dry today.”

As usual, Vanilla was in the back alley puffing on a cigarette. She took one look at my face and immediately started in on me.

“That little sister of yours… she sounds like a real femme fatale.”

“A femme fatale?”

“A monster that drains your life force.”

She might not have been wrong.

Whenever I had sex with Mii, it left me utterly drained. It felt like I was losing control of both my mind and body, as if I were being pulled apart. Putting myself back together afterward required a terrifying amount of effort. I still felt like I was carrying the weight of the hangover from two nights ago.

“Do you hate her?” Vanilla asked.

“It’s not that. It’s just… something feels off. I don’t know how else to put it.”

“Off, huh?”

“That’s the only way to describe it.”

“Could it be, Saki-kun, that you’re thinking about your ex while you’re inside her?”

“…No. Of course not….”

“There was a gap there. Yikes—that’s cold.”

Vanilla pulled a face, looking genuinely repulsed.

“The sister definitely notices. It’s hurting her. I bet she’s thinking, ‘Right now, he’s thinking about my big sister,’ while you’re at it.”

“Maybe. I can’t deny it.”

“Stop doing that. It’s gross. How long ago did you date the other one?”

“Five years ago.”

“Did she dump you?”

“Harshly. To put it lightly.”

“And you still love her?”

“I don’t think that’s it.”

I shook my head, and Vanilla tilted hers, looking puzzled.

“You don’t think? What’s that mean?”

“I can’t really explain it.”

Vanilla looked unconvinced, but she exhaled a cloud of smoke as if giving up on the line of questioning. “Well, sounds like a messy love triangle. Though, I’m pretty sure most of the blame lies with you, Saki-kun.”

“I’ve got no defense.”

“You should just kick her out. Sex without any real feeling just makes everyone miserable.”

“I can’t do that. Or rather, I don’t want to.”

“Because you slept with her?”

“No. Well, yes, that’s part of it. But even without that, I can’t just abandon her.”

“Is she someone important to you, outside of the sex?”

“She’s far more important to me without the sex.”

I remembered when we played together most—back when she was in elementary school. Me, my childhood friend, and Mii. We’d gone to the local summer festival, and I still remembered the weight of a tuckered-out Mii on my back as I carried her home.

Now, that same girl was the one riding on top of me.

It wasn’t funny.

“You’re just letting things drag on,” Vanilla said.

“I know. I really do.”

“Careful, or she might end up taking more than just your energy.”

“Do I look like I’m in that much trouble?”

“From where I’m standing, yeah.”

“Honestly, I want to do something about it.”

I knew this wasn’t right. Living a life of pure indulgence with a runaway like Mii—if my high-school self heard about this, he’d be horrified.

“Is there any way, Vanilla-san, to keep her around without having sex with her?”

“What a ridiculous problem.”

“I’m being serious.”

“It’s simple, isn’t it?”

Vanilla stubbed her cigarette out in the ashtray and stood up, stepping in front of me. As she moved out of the shadows, her blonde hair caught the light, reflecting a pale, almost white glow.

“Just clear your head beforehand.”

“Meaning?”

“I mean, make sure you aren’t tempted by her.”

She undid her top button. Reaching deep into the front of her outfit, she pulled out a single card.

“Here.”

It was a business card for a shop.

“Where were you keeping that?”

“The inner pocket. Sexy, right?”

“Is this… a massage parlor?”

“A friend of mine runs it. It’s a ‘safe’ place. I’ll give them a heads-up, so just go.”

The look in Vanilla’s eyes was teasing, as if she were enjoying my discomfort.

“Special discount. No request fee. Thirty percent off.”