Back home after a long time, I find my younger sister, now a high school student, just as affectionate as she was when we were kids—cuddling up to me in that sweet, innocent way that makes my heart race. Recalling her matured body becomes too much for me, a virgin who moved to Tokyo without ever losing my innocence. The moment I return to my room, I can't help but jerk off, reliving the sensation of touching her. Before I can finish, she walks in, catching me red-handed. I try desperately to hide it, but she's standing there with no bra, her nipples clearly visible through her shirt, and I can't control myself anymore. Surprisingly, my sister is completely open about sex—she even laughs and offers to help. Realizing I'm still a virgin, she gently takes the lead. When I finally enter her, her pussy feels so amazing that despite being a first-timer, my hips start thrusting on their own, launching into intense, deep strokes. Even this experienced, sexy gyaru sister starts cumming repeatedly, overwhelmed by pleasure. Watching her climax over and over from my virgin cock drives me wild, making my thrusts even faster. "Onii-chan's dick is incredible..." she moans, trembling through orgasm after orgasm, looking cuter than ever. As a virgin, I lose track of control and might've cum inside her without warning... Sorry, sis.