 The track is a midtempo ballad and, like "Pureness," it was written, composed, arranged and produced by T2ya.It was recorded by Ueto on September 13, 2002, the day before her seventeenth birthday.At the time of release, Ueto was in the middle of filming her first feature film, "Azumi" (2003), and had to learn the lyrics to "Kizuna" on the day of recording.