Haruna Masaomi is a man in his early sixties who lives in the small countryside village of Higashikawa. His wife, Mariko, died several years prior, and the couple never had any children, leaving Masaomi on his own. Masaomi regrets not having any children, but he has made peace with his secluded life, and he’s happy enough whiling away his remaining years reading murder mysteries… At least, until he meets a young girl collapsed in his garden late at night, during a thunderstorm. Masaomi doesn’t know where the girl came from or what happened to her, but one thing is clear: she’s no ordinary human. With horns like hers, and long, sharp claws, she can only be a monster. Ignoring the warnings of his housekeeper, Masaomi decides to take the girl in — but what will happen next?