Umekichi Kadomori is the second son of Taiju Kadomori, head of the Kyoto-based Kadomori house. The family faction serves as Guardians of Kyoto, specifically managing interactions between humans and tsukumogami spirits. Within this role, Umekichi formally holds the position of Guardian alongside his family.

His eldest brother, Taiju Kadomori, uses the nickname "Ume" for him. Umekichi's immediate family also includes an older brother named Shota Kadomori and a sister named Tsubaki Kadomori, all involved in the family's spiritual affairs.

In combat, Umekichi specializes in physical engagement, mastering direct fistfighting techniques and employing spiritual sealing methods. He also utilizes unconventional tactics, strategically manipulating his clothing fabric during battles for advantage.

Outside of combat, Umekichi shares a religious role as a preacher with his older brother Shota, though specific doctrines or practices remain undocumented.

His name reflects symbolic elements: "Ume" originates from the Japanese term for plum or apricot, while "kichi" signifies luck or goodness. The surname "Kadomori" translates literally as "gatekeeper," directly aligning with his family's protective function in Kyoto.