Captain of the Konoha Medic Corps

He is the chief medical officer of the Konoha Medical Unit Squad in Konohagakure and the adoptive father of Kabuto Yakushi.

Background
After the Battle of Kikyō Pass, he found Kabuto amongst the dead enemies and brought Kabuto with him back to Konoha, raised him as a son, and taught him medical ninjutsu when he got older.