Rin, a brother who loves older brothers, is itching to have sex with her older brother, but her common-sense older brother doesn't see his younger sister as a sexual object at all. ``That's right, you can use an aphrodisiac!'' Rin is inspired and commits an outrageous act of dousing her brother in an aphrodisiac! The aphrodisiac causes her brother to lose his mind and his erection doesn't stop, and the younger sister who loves him has sex!