Comes as a blank CD, a sticker, and a lyric sheet to a song called regret. This song was made by the band ruvish but in collaboration with Reon and HIRO. They called themselves: イブクロ (Ibukuro). Not much is known about this group but seems like it was one time session. This was live distributed at a free Ruvish live event in Meguro Live Station

Credits to the song regret:

Song by: ジョン・レオン (John Leon)

Musician: へろ(HIRO)

Lyrics and Song: へろ (HIRO)

Vocals: REON (Ruvish)

Band Name: イブクロ (Ibukuro)