In May 2009 Kotoōshū announced his engagement to 29-year-old Asako Andō from Ichinomiya, Aichi, whom he had dated for the previous five years. The first time he became acquainted with her, he called her at a convenience store in Nagoya in 2004. A long-distance romance going between Chiba and Aichi continued for five years until he proposed. The following February, had a ceremony at Hie Shrine (Chiyoda-ku). They married in February 2010, on St. Valentine's Day, at the New Otani Hotel in Tokyo, with around 600 guests including "yokozuna" Hakuhō attending. Kotoōshū acquired the surname of his wife and his official name became Karoyan Andō. They welcomed their first son, Kiril Andō, in November 2011.