My shut-in little sister. To me, she was just part of the background. Wearing the same worn-out T-shirt for years. Stretched-out sweatpants. Tissues and smartphone charging cables scattered across the floor. Her eyesight is poor, and she's bad at talking to people. Since she never goes outside, she's naturally a NEET—what you'd call a "mojo girl." We're siblings. So, I didn't really have any interest in her.
──Or so I thought. That day, I opened the door to her room for a small errand. I didn't knock. I never did. What unfolded before me was a truly shocking sight. My sister was desperately biting down on her shirt, her hips lifted off the bed. I saw something I wasn't supposed to see. My mind went blank in an instant. What was most shocking of all was her face. Usually, she has dead fish eyes and just stares blankly at her phone, but now she had an expression as if she were drifting far away, yet desperately clinging to something.
My reason crumbled with a loud crash.
The boundaries of being a brother, all of it, vanished.
By the time I realized it, I had entered the room and was hovering over my sister. I pinned down her resisting arms and forcibly pulled her trembling body close. I didn't even know what I was doing. But I couldn't stop anymore.
And then──my sister's body, which I thought was as dried up as a piece of jerky, was incredibly hot and wet. I lost myself, moving my hips. So relentlessly, so deep, that she didn't even notice she was cumming.
"Please, enough... I'm... I'm cumming..." Even those words sounded distant. Again and again. Every time I pierced her depths, my sister's fingers gripped the sheets. She let out a voiceless cry and trembled slightly again. Still, I couldn't stop...