Zatch Bell!

🇯🇵金色のガッシュ!! · Konjiki no Gash!!

MangaShounenFinished🇯🇵 First published in 2001ActionAdventureComedyFantasy

Makoto Raiku story, art

Kiyo is a brilliant junior high student whose inflated ego (and tendency to blow the grading curve) has made him a major target for teasing at school. So his father sends him a bizarre birthday present – a strange little boy named Zatch Bell – to help him make friends and reform his bad attitude.

Synopsis via AniList