Black Bunny but is drawn as brown, Kurousa is Shirousa's twin brother and, along with Shirousa, specializes in making Pastries, (Cakes, Cookies, etc.). He and Shirousa befriended Sophia when he and his friends are transported to the human world. They assist her in helping her to bake because she doesn't know how.

http://en.wikipedia.org/wiki/Sugarbunnies