Vampolfo (Vampiro "Ivan" II in the animated version) is the main antagonist of the Monica's Gang episode, Um Amor Dentuço. He is a vampire boy who wants to transform Monica into a vampire to make her his fiancé.
Vampolfo originally was a lonely vampire. In one of his night flights, he saw Monica chasing Jimmy Five and Smudge after being provoked by them when he sees Monica for the first time he falls for her. Seeing Monica get tired during the chase and he appears to help using his dark powers to possess the minds of Jimmy Five and Smudge and scares them.
Then Vampolfo bites Monica's hand pretending to be kissing, thus poisoning Monica for her to transforms into a vampire. However, Jimmy Five, Smudge and Maggy are the ones who discover that Ivan is a vampire and that Monica is in danger.
Jimmy, Smudge, and Maggy join forces and try to save Monica of Vampolfo, but all their attempts to defeat Vampolfo fail miserably. However, he is defeated when Monica beat in him to save his friends of Vampolfo. Ivan goes away sad, and Monica along her friends manage to escape his mansion.