The group consists of Kimiko and Jun Sasaki, who were classmates at high school in Chiba, Japan.
Since they were independent record label artists, they had performed in great number of live shows, including a nationwide tour of 63 shows in 3 months, and their major label debut on September 22, 2010.
They have composed and sung the theme songs of TV animation, such as "Hanasaku Iroha," "Non-Non Biyori" "Bakuman," "Food Wars!", and also NHK's "Minna no Uta" and "Summer high school baseball broadcast".
They also compose songs for other artists and active in a wide range of fields. They continued to expand their musical activities, including a one-man live tour of 47 prefectures, planetarium performances, and festival appearances at
ROCK IN JAPAN and COWNTDOWN JAPAN. In 2025, they released their 8th full-length album for celebrating the 15th
anniversary of their debut.