Yohei Umino is the adoptive father of Nagi Umino and biological father of Erika Amano and Sachi Umino. He co-owns and manages a restaurant with his wife, Namie Umino. Both were high-school delinquents, a shared past that forged their bond and led to marriage. This background fuels Yohei’s more overtly volatile temperament compared to Namie’s, evident during family tensions like a restaurant confrontation with Erika. Despite this edge, he shows consistent kindness and care toward all three children. Fishing is his chosen hobby, providing a temporary respite from daily stresses. His appearance is distinctive: blond hair with shaven sides, frequent sunglasses, and a signature outfit of a red button-up shirt, ash gray pants, black leather belt, and black shoes. The kanji in "Yohei"—"洋" (ocean) aligns with the Umino family’s water-themed names, while "平" (calm/peaceful) contrasts his fiercer disposition. Astrologically, he is a Leo. Juggling restaurant duties and parenting, Yohei navigates complexities from the switched-at-birth revelation involving Nagi and Erika. His marriage to Namie remains affectionate, though their arguments occasionally echo their delinquent history.