PPPE-275 [Uncensored Leaked] I defeated my obedient big-breasted sister in an erotic game, so I made her wear a lewd costume and conquered her breasts, then I fucked her raw.

Yuu, a social misfit and NEET, stays at home and spends his days engrossed in erotic games. He has always wanted to try out the erotic play he has developed through playing erotic games, so he decides to try it out on his cheeky younger sister as an experiment. They compete in an erotic game, and the penalty game is that the winner must do whatever the other person says. Yuu wins by a landslide, and then he makes his busty sister wear an obscene costume...