Cloud-on

Cloud-on is one of Nana's animals which looks a cloud with black eyes and a mouth. Apparently, its unique ability is to throw a ray. Cloud-on throws a ray to Yami attacking Rito. It appears in the chapter 46 of Darkness, Nana uses it for avoiding Darkness Yami attacking Rito. It seems to be based on a character of Concerto Gate, an MMORPG game in 2007, because of the same physical appearance and the same name.