Mona the Vampire: Angela Smith

Angela is Mona's snobbish rival in the series. Often, Angela boasts about her wealth to her classmates and often enlists George in her schemes to cause problems for Mona. Her parents won the lottery and spoil her rotten.

Mona the Vampire: Lily Duncan

Lily is Mona's second best friend. Before she was a quiet, shy girl who had her hair covering her eyes. She soon became Princess Giant, a braver and stronger version of Lily (a secret identity suggested after Lily expressed the rather boring idea of being 'big' as a characteristic superpower). Lily once fell in love with a cartoon character. She has also been in troubling situations such as when Frankenstein was going to transplant her brain. In an episode involving a werewolf, she refused to be used as bait in a trap for the beast, insisting it was sexist and leading to a reluctant Charley being used instead.