Zannin was one of the main villains from the Devilman anime series. He was the second-in-command of Zennon and had many demons serving under him. He was the first of three Demon Generals who worked for Zennon and easily the most iconic. Zannin was a gruff, sadistic and quick to anger demon with a hatred more to Devilman rather than humanity itself. He disallowed failure and would happily kill those who fled from battle although he did so several times himself, this led to him being incredibly unpopular and hated amongst his fellow demons.

(Source: Devilman Wiki)