Mizuki Amane came to stay with her older brother in Tokyo while preparing for her university entrance exams. Tired from studying, she lies down in her school uniform and falls asleep without changing. While she's unconscious, her brother returns home and can't help but stare at her defenseless body. As he watches her sleep, he moves closer, peeking at her panties and sniffing her hair, gradually growing aroused until he pulls out his cock and starts jerking off. He begins sniffing her feet when suddenly Mizuki wakes up in shock, screaming, "Onii-chan! What are you doing?! We're siblings!" Panicked, she apologizes repeatedly. But instead of pushing him away, she feels sorry for him and offers help. "You've been holding back so long, that's why you lost control. If you promise not to do it again, I'll help you just this once. What do you want me to do?" Her brother asks for a footjob. He's obsessed with her black pantyhose, the way her panties look through the fabric, and the sweaty scent of her stockings. Oblivious but obedient, Mizuki begins giving him a footjob through her pantyhose, but he doesn't cum. "I'm almost there... if you show me your breasts." His demands escalate—first her hands, then her mouth. Still, he can't climax. Finally, Mizuki suggests, "We can't have sex because we're siblings, but just rubbing together should be okay. Come inside me like that." She removes her panties, straddles him, and grinds her pussy against his cock. To her surprise, she starts getting turned on, desperately suppressing moans from escaping. But the slippery wetness dripping from her pussy is impossible to hide. Their movements grow wilder and faster until suddenly, his cock slips inside her wet slit. Neither can stop now. Overcome with pleasure, her brother cums deep inside her pussy.