The fallout from Piro's and Nanasawa's first argument. Piro discovers that Nanasawa's insane fanboys know where she works and will mob her when her shift starts. To help her out, he poses as a busboy and uses his knowledge of fanboyism to keep them from taking lewd pictures of her. When she figures out what they're doing, Nanasawa is horrified and furious, since she'd previously spoken against the assumption that fanboys were a bunch of creepy stalkers, and that's just what these ones were. When her shift was over, she took out her anger on Piro and yelled that he probably thought he only did it to get in her pants. Then, she broke down on the train ride home. Ouch. And it only really hit her how awful she had been when Piro finally says something back to her.
Piro: I didn't deserve that. [train door immediately shuts between them]