Mitsudomoe

Newly hired teacher Satoshi Yabe begins his job teaching class 6-3 and soon becomes aware of the terrible Marui triplets, Mitsuba, Futaba and Hitoha. When the triplets notice Yabe might have a crush on the new school nurse, Aiko Kuriyama, they purposely try to injure his groin in the hope that Kuriyama will like what she sees. When Yabe incidentally gets injured after running into Kuriyama, she confuses him for a fourth grader (she's blind without her glasses). Yabe gets the class a pet hamster, which Hitoha names Nipples and becomes attached to. When others start to play with her too much, Hitoha starts becoming defensive.

Futaba catches a cold and ends up ensnaring Yabe into a rather long and sticky booger. Hitoha gets access to Yabe's apartment in order to see Nipples outside of school, blackmailing him from making other arrangements.

A boy named Yuudai Chiba catches a glimpse of Hitoha's erotic book and wants to see more of it, his friend Shinya Satou getting confused and assuming she wants to see her panties. Through certain events, Hitoha ends up meeting occult fanatic Sakiko Matsuoka, who mistakes her as being able to see ghosts. They end up sneaking into the pool before it opens, with Sakiko assuming Hitoha is trying to exorcise spirits, when she is actually drowning. During swimming the next day, the triplets forget their underwear and jump to the conclusion that they were stolen. When their suspicious looking father, Soujirou, arrives at school with the panties, Mitsuba is too embarrassed to admit losing them and implies he is the thief, getting him arrested.