Summer vacation! Seiji, Guri, Akane and Yuzu have invited Akua to go with them to the beach. Akane tries to get Akua to go swimming with her in attempt to get closer to Seiji's little sister, but Akua gives her the cold shoulder. Pouting at her brother and his harem Akua goes to swim by herself but a dark shadow looms beneath her. Meanwhile, summer also means tests of courage! Guri suddenly invites Seiji, Akane, and Yuzu to the school after dark for a test of courage but her real motives are to pair another young couple who have asked for her help. Seiji thinks something isn't quite right about the pair though...
Uh, our ideas of fun are different...
Unter Spaß verstehe
ich was anderes.
Nuestras ideas sobre la diversión
son diferentes.
No pensamos igual sobre la diversión.
C’est pas une obligation…
Abbiamo un'idea diversa di "divertimento".
Nossos conceitos de diversão 
são meio diferentes.
И это, по-твоему, весело?..