Don't Call It Mystery: The Movie (2023)

Kuno Totono is a college student with naturally curly hair. He is extremely smart and loves curry, but doesn't have any friends or a girlfriend. Kuno Totono loves to talk and he can often solve difficult problems simply by talking it through. One day, Kuno Totono visits the city of Hiroshima. There, he gets involved with a mystery involving the succession of the Kariatsumari family’s property.

(Source: AsianWiki)

Adapted from the manga "Mystery to Iunakare" (ミステリと言う勿れ) by Tamura Yumi (田村由美).