Now that he's had sex with another girl, Yuko, he realizes that he can't bear to be around her anymore. He's also worried about how he'll look when he gets back to school. He tells himself that he won't be able to stand on his own two feet anymore, and that he will have to take off his clothes and go to the mall all the time. He also realizes that his legs are beginning to ache from the slaps they've just received from Yuko. He realizes that Yuko has been using his legs as leverage to get her to have sex with him, and now he can barely stand on one of them.