Akuma-kun
Japanese title: 悪魔くん
Alternative titles: Devil Boy
Type: TV
Source: Manga
Episodes: 42
Status: Finished Airing
Aired: Apr 15, 1989 to Mar 24, 1990
Broadcast: Saturdays at 19:00 (JST)
Duration: 25 min per ep
Rating: G - All Ages
Studios: Toei Animation
Genres: Adventure, Fantasy, Horror, Supernatural

The age of the demons has begun. Dr Faust has foreseen this rise of evil. Unfortunately, he is near death and is unable to personally battle this upcoming threat. Faust entrusts a young boy, Shingo Yamada, to take the responsibility of ridding the Earth of this new evil presence. Faust finds a birthmark on Shingo's forehead that signifies that he is the chosen demon fighter. Faust summons from hell what may be humanity's only hope of surviving: a less than enthusiastic devil named Mephisto rises. After signing a pact in blood to save humankind, Shingo and Mephisto set out to battle the supernatural world.

(Source: AniDB)