Sensei pretends to be an employee to keep Io and himself out of trouble since the girls of the second dorm are using the bathhouse due to a broken water heater. He suggests to close the bathhouse early and she doesn’t mind doing it as they already made more money than usual. More customers come in, but when Io wants to inform them that they’re closing, she notices that it’s Yuki who came together with Sara. Sara is surprised to see him here, but Yuki explains that he is rocking the cradle. He tells them that he’s working for Io tonight, which irritates Sara, because he never works for her, and enforces Yuki’s argument. Sara doesn’t mind as long as he doesn’t Io doesn’t share her fate and tries to talk with her, but since it’s Io, it doesn’t go well.
Because she knows that Yuki likes to bathe alone, Io offers them the men’s side, but Sara suggests that all of them, including Sensei, bathe together. Yuki reminds her that this would be inappropriate since Io is Sensei’s student, but she doesn’t see an issue as long as everyone is wearing swimsuits. Io isn’t sure if they have any but also wonders why she should join them. Sara thinks that she would like to relax with them now that her shift is over. Sensei agrees under this conditions and Io agrees as well, knowing that Sensei would join them even if she refuses. She goes upstairs to find some swimsuits and reminds them that the bathhouse is under surveillance, which concerns Sara while Yuki is used to it.
Sensei decides to wait outside the changing room while Sara and Yuki get undressed, but he gets pulled in by Sara, who only wears a towel, and Io isn’t surprised by that once she’s back. She informs them that she only found shorts for Sensei and her own swimsuits, so the girls have to keep their towels on. Sara “accidentally” loses her towel, something Sensei saw coming, and teases him with that. Yuki doesn’t bother to fight against it and drops her towel as well. Io gets uncomfortable while Sara is happy to be the biggest for once. Io forces the girls into the bath so Sensei can change his clothes.
He joins them shortly after and acknowledges that both Sara and Yuki have their suspicions about him, but without solid evidence and nothing going to happen tonight, he isn’t worried about that. After a conversation about the girl’s respective tattoos, Yuki wants to know if they heard about Yumi as she got a hint from a former biker friend that she returned to her father’s home. Io tells her about Yumi’s fight in class, which makes her proud of her daughter, while Sensei has nothing to add since he doesn’t know more than her. Io wonders why she did it, thinking that Yumi wouldn’t hurt someone without a reason, but Yuki doesn’t care and mocks Sara for her tattoo again, which ends with them fighting while Io tries to hold hands with Sensei now that they aren’t watched, but he doesn’t let her.