Prince Monster is the the vampire Prince of all Monsters.
Prince Monster came to Trampire's Castle requesting that Trampire has her servants find him a human girlfriend from Penguin Village. The minions bring back Arale, who Prince Monster ends up liking alot. Though, Arale did not follow the qualities of an ideal human girl such as beautiful singing. He ends up liking her even though Arale destroyed the castle with her N'cha Cannon. Prince Monster ends up leaving, but gives Arale his autograph.