Koi (恋; Love) is a digital single by Kikkawa Yuu. It was released on May 1, 2019, the same day as Kikkawa's 27th birthday and the start of the Reiwa era.
It is a two-part work with "yoake", which tells different love stories about the same protagonist.
- Koi (Instrumental)
- Lyrics: Rihi
- Composition: Okuwaki Tatsuya
- Arrangement: Matsui German Jr., michitomo
- The cover is a collage of Kikkawa's childhood photos from when she had her first love.