Beelzebub (Demon Monster Girl)

She has two forms. Her humanoid form has, like most demons, white hair and crimson irises with a cloved tail, with white horns and what appear to be chitin spikes jutting through her hair. Beelzebub wears an almost completely crimson outfit, with a black undershirt, a crimson waistcoat, crimson gloves, and a long crimson blazer. She wears a lot of fly-type trinkets, bracelets, and jewelry

Beelzebub in her humanoid form exhibits a grandiose and self-absorbed personality. Lucifer describes her as the most dangerous demon and that's why she was sealed.