Sunao Moriyama encounters a strange but cute creature, which he names Potemayo. Potemayo follows Sunao everywhere, often perched on top of his head. The discovery quickly becomes a topic of interest among Sunao’s classmates. Shortly thereafter, another similar creature appears and is given the name Guchuko by one of Sunao’s peers; unlike Potemayo, Guchuko does not seem to be as good‑natured.