The main character, Ranze, is a junior high girl with troubles: her father is a vampire and her mother is a werewolf. Ranze has yet to manifest her supernatural powers, and her parents are beginning to get worried she might be normal. So begins the fantasy romantic comedy story.

A boy living in Wakayama Prefecture accidentally comes into possession of an Adélie penguin egg and successfully hatches it. However, wanting to return the penguin to its natural habitat, he embarks on a journey to Antarctica. Along the way, in Central and South America, he faces hardships, such as being robbed by impoverished local children. The story is framed as the recollections of Ryota Ichik...