Sebastian is charismatic, unafraid of detention and breaking rules. He was undaunted and determined to pursue his goals, always unbothered by defeat. He was willing to use the Dark Arts to help his sister and justified it with her condition. He did not view magic as good or evil, but rather a tool to achieve his goals. He was optimistic, a trait his parents also had. He relied on their memory to stay open-minded and persistent, pursuing and using knowledge as a guide.