Kuroba Ayako (黒羽 亜夜子) is a member of the Kuroba Family, a Branch Family of the . She is also a second cousin to the siblings. Excluding the short cameo during the Reminiscence Chapter, she first appears in Volume 11 as Yotsuba Maya's representative during her talk with Colonel Balance and another time when facing Kudou Retsu. She has a twin brother, Fumiya (文弥), who is one of the candidates to succeed the Yotsuba head position, alongside Miyuki.