Minatomo-san is a traveling carpenter (in)famously obsessed with repairing any broken door he sees. A native of Wano Country, he left with Shimotsuki Kouzaburou and Furiko 55 years ago and resettled in the East Blue. One of his relatives, also known as Minatomo, remains in Wano.

He originated in the SBS as a joke used by Eiichiro Oda to “explain” an art oversight in Chapter 1 (namely, a door at Partys Bar reappearing intact minutes after Higuma kicked off its hinges). Since then, the anime has periodically used him as an Easter Egg (not unlike Pandaman) in crowd shots and the like. Interestingly, he has never appeared in the manga proper, with even an identical carpenter in the Wano Country Arc identified as a separate person.

(Source: One Piece Wiki)