Deceiving a rebellious, big-breasted girl whose only growth is physical penetration and then ejaculating inside her without a condom! ~Pleasure control punishment for lacking sex knowledge~ Nono Mitsuru FPRE-034

My parents remarried, and I gained a stepsister. Mitsuha, from the J department, is a rebellious teenager who seems to hate me. Although she's arrogant, she has a large, voluptuous body and appears feminine. However, this younger sister often exposes her underwear and even her body, seemingly unaware of sex... I, the older sister, take advantage of her ignorance, controlling her pleasure and turning her into my sex toy! "You're awful! Why would a brother do something like this?" "Mitsuha, sex is so wonderful!"