Konjiki no Gash Bell (Manga)

For his 14th birthday, Kiyomaro received a strange little boy named Gash Bell as a bizarre gift from his father. Kiyomaro soon discovers that there's more to Gash than his dad ever realized--Gash is a child from another world with magic powers that are unleashed by reading spells from a mysterious red book...and there are 99 other kids like Gash who must fight one another to become the king of that world!