 On December 18, they made their first appearance with the song .On February 8, 2012, they made their major debut with their single "Study x Study", which is used as the ending theme to the 2012 TV anime "High School DxD".Their second single "Miracle Rush" was released on May 16, 2012 and is used as the opening theme to the 2012 anime "Saki Achiga-hen Episode of Side-A".