sleepy.ac is an alternative name of sleepy.ab coming from their newest acoustic live album "sleepy.ac「LIVE@Sapporo Kitara」". "ac" for acoustic instead of "ab" for abstract. sleepy.ab is a four-piece post-rock band from Hokkaido, Japan formed in April 2002. They describe their music as having characteristic melodies of transparency and floating aimlessly. sleepy.ab members are: 成山剛 (Tsuyoshi Nariyama) on vocals/guitar , 山内憲介 (Kensuke Yamauchi) on guitar Read more on Last.fm