Yoshikawa, a student who is retaking entrance exams, is in a difficult situation. Aina, the woman he admires, always greets him in the hallway of his apartment. His luck ends when he accidentally opens a package addressed to Aina. Aina buys him a front-hook bra to solve her nighttime troubles, and he has to give her his opinion of the underwear. "Don't peek at me while I'm changing." Yoshikawa, who could only do this in shock, comes to his senses and hurries after Aina, but he can't help but peek at her while she's changing.