Beelzebub

ベルゼブブ

A childhood friend of Azazel who belongs to an elite family of demons. Although he appears to be a bird, he is actually a fly demon who eats feces, much to the disgust of those around him. He also possesses an ability called Divulgence, which grants him the power to make others reveal their hidden selves, ranging from exposing the side of themselves they do not want people to see, to forced defecation. He can also use goat dung as a doping drug, making his attacks considerably more powerful.
In the 3rd OVA, it is said that his full name is Beelzebub Yuuichi.