Joseph is a selfish, insecure, self-absorbed young man who still suffers from grief and trauma from the death of his mother, and from Cameron turning him into a Vampire after killing his mother when he was a young boy. He is hell-bent on revenge against Cameron, who accidentally killed his mother, Christina, when Cameron suddenly transformed into a Vampire Guardian Angel after being bitten in Heaven and falling back to Earth. But Joseph was not aware that he was a reincarnated Guardian Angel, called "The Killer of Angels" for his power of light that could send Angels to their deaths and resurrection back in Heaven.
Joseph still cannot find himself to forgive Cameron, and his anger is so great that he is contemplating joining forces with whoever can destroy Cameron, even if it means finding an ally in Gabriel, who is still vengeful about what Joseph did to him but he hates Cameron more, or by leading the Vampire Guardian Angels himself. In the process, Joseph finds his desire for power growing. But he knows he is inexperienced and still young and that no one takes him seriously, and he is resentful of that, and it makes him insecure and more determined to prove himself. He also wants to be more powerful than Gabriel and Cameron, and resents Cameron’s pleas for him to “stay good”. Like Janos and Gabriel, Joseph is so traumatized he can no longer feel much human emotion, and Cameron is determined to make Joseph hang on to what little empathy he has left.
Joseph is highly intelligent and unlike Janos and Gabriel, he is not reckless and impulsive. He plans before he acts. He knows he has incredible power that he still needs to learn how to use, but is undecided whether for good or for evil. He is ambitious and intuitive and also very secretive. He watches and learns, and tries to find vulnerability. He finds ways to use people and situations to his advantage. He sees himself as a better leader and no matter how difficult, he is focused on that goal and on gaining the respect of all the Vampire Guardian Angels. He is actually fearless, courageous, and willing to find ways to achieve his goal. He can be stubborn and confrontational, and likes to be in charge and does not want to be told what to do. Deep inside is a brooding passion for a challenge and he seeks to discipline that energy and make it work for him, which makes him a formidable contender for future leadership.