Beelzebub

Japanese name:

ベルゼブブ

A childhood friend of Azazel who is apart of an elite family of demons. Despite appearing to be a bird, he is actually a fly demon who eats the feces much to the disgust of those around him. He also has an ability called "Divulgence" which gives him the power to make others reveal their hidden selves ranging from revealing the side of them they don't want people to see, to forced defecation. He can also use goat dung as a doping drug, making his attacks considerably more powerful.

Wikipedia