After losing his mother who he was close to (and who spoiled and over-protected him ever since Gabriel went after him as a child), Joseph is driven by the desire to be loved, and even admired. He wanted to be the center of attention, and often acted out against Cameron, a cop, by trying to become a juvenile delinquent. It was his cry for attention, and it led to depression and hate after he found out that Cameron was responsible for his mother Christina’s death.
Joseph was once a happy, helpful, big-hearted child who was for a brief time, close to Cameron. They almost had a genuine father-son relationship as Cameron was dedicated to protecting Joseph from Gabriel. Even though Cameron disappeared from Joseph’s life for a period of time while bringing Gabriel back to Heaven, Joseph still loved his stepfather and looked forward to him. That all changed after Christina’s death.
Although often wallowing in self-pity and anger at what he felt was Cameron’s betrayal, Joseph is hardly disheartened by disappointments and setbacks. It only makes him more determined and headstrong. But he also becomes overconfident, his ego gets the better of him when he reminds himself and others that he once killed Gabriel, although it was also by chance and now, Joseph can hardly even defend himself or wield a sword. He is still too untrained with his own powers.
Unfortunately, Christina’s death also caused some deep emotional and psychological damage to Joseph. He is unable to have a relationship with the opposite sex as he sees too much of his own mother in them. As a teenager, he could never look at a girl his age, or even have a physical relationship, without seeing the likeness of his own mother. So he is often alone and unable to develop feelings for anyone. He almost had an interest in a female vampire, Catharina, but she was killed by Jeromos. Even her saving his life did not cause Joseph to develop any feelings other than hate and desire for revenge. He remains often cold and unemotional.
Joseph also has a huge and fragile ego, and he gets hurt over the most trivial of things. But he wants so desperately to destroy Cameron that it blinds him with rage, and he often loses control of his own situation. His impatience leads to uncertainty and anxiety and he becomes unsure of himself. He is also extremely envious of Jeromos and he desperately wants power and to be better than who he sees as his enemies.But being the youngest of the Vampire Guardian Angels he hardly has any experience in weaponry, self-defense or leadership. He desires above all to have a father figure but can never get close enough to anyone to do so. And to the Vampire Guardian Angels, Joseph is just an annoying young adult, barely intimidating. However, they know Joseph is also widely feared because of his growing power of using light to destroy Angels, and he still is in danger of being destroyed by Gabriel and by the angels. And he is still not at the point where he is respected.