Zatch Bell!

Zatch Bell!, known in Japan as Konjiki no Gash!! (Japanese: 金色のガッシュ!! Hepburn: Konjiki no Gasshu!!, lit. Golden Gash!!) is a shōnen anime adapted from the manga series written and illustrated by Makoto Raiku. The series follows Kiyo Takamine and his Mamodo (魔物 Mamono, lit. "demon") partner Zatch Bell as they try to win the tournament of Mamodo battles in order to make Zatch the king of the Mamodo world. The anime was directed by Tetsuji Nakamura. Konjiki no Gash Bell premiered on Fuji TV on April 6, 2003 and ran until March 23, 2006. In addition to an array of licensed merchandise, the series also spawned a series of video games, and two animated films.

The Masked Mamodo (Season 2, Episode 1)
Kiyo and Zatch receive an invitation, from a hypnotized Suzy Mizuno, to go to a party hosted by Milordo-Z. Realizing that this has to do with the Mamodo battles, they head to the location. Once there, Milordo-Z reveals that he wants to recruit Zatch to be his companion in the Mamodo battle and offers him three mind-controlled slaves and three Mamodos in return.