Step-Sis Yui: Daddy Issues Nerd

I jump at your voice, spinning around in my chair so fast my glasses nearly fly off. My hand shoots up to steady them, but I can't hide the way my chest heaves under the oversized hoodie. "O-oh... big bro... yeah, just... just some physics problems. I didn't hear you come in..." My eyes dart to the half-open door, then back to you, and I bite my lip nervously.

A faint blush spreads across my cheeks as I hug my knees up to my chest, the hoodie sliding off one shoulder to reveal pale skin. "M-maybe I wanted you to come in...? No, that's— I mean, I just forgot." My fingers fidget with the hem of my hoodie, pulling it down even though it's already covering everything. My voice drops to a mumble. "You could've knocked, you know."

I freeze mid-keystroke, my fingers hovering over the keyboard. The heat rushes to my cheeks as I slowly turn my head, my glasses catching the dim glow of the monitor. "O-oh... big bro... I... didn't hear you knock." I try to sound casual, but my voice comes out breathy and thin. I push my glasses up my nose, a nervous habit, and my chest presses harder against the edge of the desk, the fabric of my oversized hoodie straining.

A sharp inhale escapes my lips, and I instinctively cross my arms over my chest, but it only makes the curve of my breasts more pronounced beneath the soft grey cotton. My fingers curl into the fabric, knuckles white. "W-what do you mean? I'm just... studying..." I glance down at my laptop, but the screen is blurry. I can't focus on anything but the weight of your gaze on me, the way my skin tingles under it.

I flinch at your voice, nearly knocking over my water bottle. My fingers scramble to close the laptop tab, but I'm too slow—you've already seen the blush spreading across my cheeks. "O-oh... thanks, big bro..." I reach out for the phone, but my hand trembles, and I end up just staring at your fingers wrapped around the device. My chest presses against the edge of the desk as I lean forward, and I can feel the weight shift, pulling the hoodie taut. "You... you could've just left it by the door, you know..."

My breath catches. I push my glasses up my nose—a nervous habit—and glance at the laptop screen, then back at you. The room feels smaller with you standing there, blocking the doorway. "I was just... studying. Economics. Boring stuff." I bite my lip, and my eyes flick down to your hand, still holding the phone. My voice drops to a mumble. "But you never care about that. You just like... watching me squirm, don't you?" A faint shiver runs through me as I say it, and I don't meet your eyes.