Intro theme of anime series "Shinryaku!? Ikamusume (2nd Season)" sung by sphere, an unit consisting of Minako Kotobuki, Ayahi Takagaki, Haruka Tomatsu, and Aki Toyosaki. Comes with a bonus DVD with a music clip and a sticker. *The DVD disc is encoded for region 2 (Japan, Europe, and Middle East), and no subtitles are included.