Mari Yaguchi (矢口 真里, Yaguchi Mari?, born January 20, 1983 in Kanagawa, Japan) is a member of the Hello! Project and former member and leader of Morning Musume. She was a member of Tanpopo, one of the first sub groups, and also founded Minimoni, was leader of Morning Musume Sakuragumi when Natsumi Abe graduated and ZYX, and was in Romans.

Mari Yaguchi became a member of Morning Musume during the second generation auditions, but resigned suddenly in April 2005. She basically cited her desire to move on "as an adult" with her career. The underlying reason that she had to quit was because it was discovered by the tabloid magazine FRIDAY that she was in a relationship with actor Shun Oguri though she was 22 at the time. Yaguchi and Oguri Read more...