Yuuichi Ootori is the first-born son of the Ootori family and Kyoya's eldest brother. As such, he's destined to become the next family patriarch upon Yoshio Ootori's passing. Yuuichi has already graduated from Medical School and works at the same hospital as his father. He is, as defined by Kyoya in the anime, the natural heir of The Ootori Group. He is married, but has dinner at the main mansion once a week to discuss business with Yoshio. In the anime, he's only seen in flashbacks when there's a close up of a photograph depicting the Ootori family men in Ep 04 - Attack of the Lady Manager! and briefly, as a younger man, in Ep 24 - And so Kyoya Met Him! In the manga, he appears only once.