Miwa Watabiki , better known by her stage name Chara (ちゃら), is a Japanese singer, actress and video jockey. She debuted in 1991 with the single Heaven. She is known for her song "Swallowtail Butterfly ", the theme song for the 1996 Shunji Iwai film Swallowtail Butterfly in which she starred, her 1997 hit single "Yasashii Kimochi", and her collaboration with Judy and Mary vocalist Yuki, "Ai no Hi Mittsu Orange". Chara later formed a band with Yuki, called Mean Machine.

"Swallowtail Butterfly (Ai no Uta)" (あいのうた, Suwarōteiru Batafurai Ai no Uta, "Love Song") is a song by Chara, released under the name Yen Town Band. It was the lead single from Montage, a concept album released for the Shunji Iwai film Swallowtail Butterfly that also starred Chara. This song was used as the theme song for the film.