"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.
Though the song is sung by Luka, some fans interpret it as being from the boy's point of view; however, this is not confirmed or supported in any way by the creator, and both interpretations would cause inconsistencies with the PV. Fans' opinions remain divided.
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.
The original upload of "Just Be Friends" reached over 2,453,000 views. The most popular reprint of the song on YouTube has over seven million views, and another has over five million views, internationally making "Just Be Friends" Luka's most popular song.
Various covers and remixes of this song have been included in additional albums. Notably, a popular remix by Masakazu Kageyama is featured in SUPER PRODUCERS BEAT. Finally, JBF RemixAlbum, a rare album released at Comiket 77, consists entirely of arrangements of the song.
The original "Just Be Friends" upload on NicoNico was undisplayed by Dixie Flatline on August 3rd, 2010 due to Yunomi-P's plagiarism, where all or part of her PVs were traced. However, Dixie Flatline has displayed again on May 11th, 2014.
Due to the nature of the controversy, its full explanation shall not be not be posted to prevent reviving old flamewars and attacks against Yunomi-P.