Kotoko's first studio album in five years, this record is the first of the two Tears Cyclone albums released to commemorate Kotoko's fifteenth anniversary in music as a major artist. All the songs included in this album are the result of collaborations between Kotoko and Kazuya Takase, one of the founders of the I've group.[1] The kai of the title is intended to mean "return", as Kotoko's return to her former music working with the I've group.[2] Kotoko wrote the lyrics and also composed 3 of the songs; Takase composed the remaining songs.
The album had no commercial singles prior or after its release; however, the song "Sign of Suspicion" was previously released as the opening theme song for the videogame Baldr Heart. For the album she also recorded "A-gain", which was originally written for former singer Ray, who released the song as her sixth single in 2016.
