Manami has four younger sisters: a set of triplets and an even younger fourth sister. When Manami orders the triplets to stay home and watch their sister, the four youngest Mitama sisters experience a truly mysterious phenomenon.
On her way to school one morning, a boy from another school gives Himeno a love letter. The sudden turn of events has Himeno bewildered due to a traumatic memory from her childhood. What happened in Himeno's past?
A new student, the Antarctican Quetzalcoatl Sassassul, transfers into the girls' school, much to the intrigue of everyone in the class. The new student is as friendly as can be, but Himeno just can't shake her fear due to a traumatic childhood experience.
Jean Rousseau of the Amphibianfolk has been frequently featured in the media lately. Just what kind of person is he? And the prominent man who has a meeting with Jean Rousseau, what strange past does this man have?
Sue-chan, the youngest of the Mitama family, has a weak constitution. Manami and her triplet sisters are always worrying about her. Himeno's niece, Shino-chan, is a very curious girl. She asks Himeno all kinds of questions as they go for a walk.
As they read a script that Mitsuyo wrote, Kyoko and Nozomi have various criticisms. Just what is Mitsuyo's story about? All the girls in the class are holding an arm wrestling tournament. Who will be the victor?