Mari Yaguchi (矢口真里, Yaguchi Mari) (born January 20, 1983) is a Japanese pop artist, actress and TV personality and former member of Hello! Project. She is a former member of Japanese idol group Morning Musume and sub-group Tanpopo, one of its first sub groups, and also founded Minimoni. She later became the leader of both Morning Musume Sakuragumi and ZYX.
She was also a member of Japanese pop group Dream Morning Musume.

Biography

Morning Musume
Mari Yaguchi became a member of Japanese idol band Morning Musume during the second generation auditions in 1998, but she resigned suddenly in April 2005. She said her reason was a desire to move on "as an adult" with her career. The actual reason she had to quit was that the tabloid magazine Friday discovered she was in a relationship with actor Shun Oguri, though she was 22 at the time. Yaguchi's TV show Yaguchi Hitori (やぐちひとり) continued as before, and she began to focus on Japanese variety shows rather than on a singing career. Yaguchi and Oguri reportedly broke up in April 2006.

In her early years in the group, Yaguchi was often perceived as being "the short one," as she did not stand out a lot. However, by the time 4th generation members joined, she had become one of the most active members of the group. Her famous catchphrase is "Sexy Beam!," one of her solo lines from Morning Musume's "Koi no Dance Site" single, and she was asked jokingly in "Joshi Kashimashi Monogatari," "When will your real sexy beam come out?" The "Sexy Beam!" line has made its way around fans and fellow musicians alike. When she resigned from Morning Musume, she was the last member to have joined before the year 2000 (Kaori Iida had left nearly two months earlier).


Post-Morning Musume
Her first post-Morning Musume recording, "Nigiyaka na Fuyu," a collaboration with Berryz Kobo, appears as the coupling track on Berryz Kobo's November 2005 single "Gag 100kaibun Aishite Kudasai."

Yaguchi starred in the Japanese drama series Sentō no Musume!? (銭湯の娘!?, "Daughter of the Public Bathhouse!?") along with fellow Hello! Project member Mai Hagiwara. Yaguchi was also one of the main actors in the Japanese daytime drama series Gal Circle (ギャルサー, Garusaa). She co-hosted her show Yaguchi Hitori, and did MCing for Hello! Project concerts. From May 25, 2007 to June 6, 2007, Yaguchi performed in Damn Yankees, a popular 1955 Broadway musical, at the Tokyo Aoyama Theater.

In the summer of 2007, Yaguchi was recruited to host the Gyao internet TV show Midtown TV, which became her third television show on air. Live broadcasts of Midtown TV aired weekdays and Yaguchi hosted on Thursdays. Mari and seven Hello! Pro Eggs appeared live and with audience on Ciao TV. With that commencing, Yaguchi was in four TV shows being aired simultaneously.

It was announced on October 19, 2008, on the official Hello! Project website, that Yaguchi, together with the entire Hello! Project Elder Club, would graduate March 31, 2009. A graduation concert was held at Yokohama Arena on February 1, 2009.


Following the popularity of singles and an album released in conjunction with the Japanese variety program, Quiz! Hexagon II (クイズ!ヘキサゴンII), Yaguchi released her debut single, "Seishun Boku/Seishun Ore" (青春 僕/青春 俺), four years after her final release in Morning Musume. She performed the song for the first time on Quiz! Hexagon II on February 25, 2009.