Onyx is a teen-aged ghost with a passion and personality that could be compared to that of fireworks. He likes to play the "bad boy" and scare people away from his room, but underneath his tough exterior, he is just a lonely boy who wants a friend. He tries to act as a "scary ghost", but usually ends up coming across as more mean and annoying than scary. Despite this, he is loyal and protective of those who manage to get close to him, and just wants to be accepted.