Toshiyuki and his wife, Chiyoko, run a store named “Fukunoya” in Fukuoka. They become friends with a takoyaki (octopus dumpling) stall owner named Tsuru and try to help her out, as does the rest of the kind-hearted community.

A man is shocked to find out that after a deadly car accident involving his wife and daughter, his wife died, but her mind somehow got transfered into their daughter's body.

Based on the TV series from the same name, Mentai Piriri stars Hanamaru Hakata, the icon of Hakata, Fukuoka, alongside Yasuko Tomita, who both starred in the television show playing husband and wife respectively. With additional scenes not depicted in the original show.

Mushi are beings in touch with the essence of life, far more basic and pure than normal living things. Most humans are incapable of perceiving Mushi and are oblivious to their existence, but there are a few who possess the ability to see and interact with Mushi. One such person is Ginko who travels from place to place to research Mushi and aid people suffering from problems caused by them.