Originally he intended on going to high school as a judo player and wanted to become a cook joining the family restaurant with his father and grandfather after graduation.

However he was inspired instead to join professional sumo after observing a practice session held by Sadogatake stable at their Kyushu lodgings.

[5] He originally took the shikona Kotokashiwadani Mitsutaka (琴柏谷 充隆) by simply adding the stable's traditional prefix "Koto" to his family name.

[11] He reached the rank of maegashira 7 in September 2019 but faced demotion to jūryō after only two wins against thirteen losses in the January 2020 tournament.

[1][26] Later in the year, during the November tournament, he withdrew from the competition after suffering a knee joint injury requiring approximately two weeks of treatment.

[27] Since many comments drew attention to the fact that he would a priori not rejoin the competition, it is expected that Kotoekō will lose his maegashira rank and be relegated to jūryō for the first time since March 2020.

His absence also marks the end of his continuous presence in tournaments, which ranked him seventh among the wrestlers with a streak of consecutive matches.

His withdrawal ended his streak of 1,043 consecutive matches since beginning his career in 2007, not including absences due to unavoidable circumstances such as COVID protocols.

[30] At his retirement press conference he shared his thanks with those gathered, adding that he had been a sumo wrestler for a long time and so felt a sense of sadness, but had really done his best with his body.

[33] Sanshō key: F=Fighting spirit; O=Outstanding performance; T=Technique     Also shown: ★=Kinboshi; P=Playoff(s) Divisions: Makuuchi — Jūryō — Makushita — Sandanme — Jonidan — Jonokuchi