Kaito Tanaka's quest for a boring life is ruined by his friends in the Paranormal Club when they drag him to investigate a slimy ghost. The ghost, a blob of green goo, latches onto Kaito. After several failed exorcisms, an annoyed Kaito yells at the creature to get a hobby.

This outburst unexpectedly transforms the slime into Shizuka, a beautiful ghost who reveals she died of extreme boredom decades ago. Finding Kaito's grumpy personality endlessly entertaining, she decides to cling to him as her new source of fun. Kaito and the club must now navigate a chaotic new life with their supernatural friend, forcing Kaito to slowly accept his new, anything-but-boring reality at the center of a supernatural comedy.