Tatt, a turtle, serves as the best friend to the main ox character running the Funny Farm. Appearing in most episodes, Tatt frequently accompanies the ox and a greyhound during their adventures. The character's shell is removable before sleeping or washing but consistently breaks apart during rough situations, particularly chaotic events involving the ox, forming a recurring visual gag.

Personality-wise, Tatt offers cautious and reasonable perspectives against the ox's impulsiveness, attempting to warn against likely doomed plans, though these warnings typically go unheeded. Gender portrayal varies: Tatt is male in the Japanese version and English dubs, while the original Dutch comics and Italian dub depict the character as female.

Official media does not address Tatt's background story, origin, family relationships, or personal history. The character maintains consistent traits and role without development across seasons, episodes, movies, OVAs, or spin-offs.