"Just Be Friends" (commonly abbreviated JBF) is one of Luka's most popular songs and Dixie Flatline's most notable work. It is about how a girl (Luka) and a boy's current relationship is going nowhere, and they start to realize their relationship is falling apart. Eventually the singer pulls the plug and breaks up with the other individual. What becomes of the broken-hearted person is up to the viewer. A reply song, "Answer", debuted at Anime Expo 2012 and was later posted on Nico Nico on July 27, 2012. It is set three years after the original song and shows how the girl has moved on.