Becoming a superhuman

You feel a very weird instinct to rob them. As you take their items, the other guy robbing them nods at you before going off, you feel guilt twist in your gut. You shouldn't have done this. But when you chose to do this you know there was no going back. As the days progressed, you kept stealing and taking things. Until one day your brother noticed just exactly what you were doing. He confronted you and you denied everything. You were turning into a true villain. A harsh person. You hated yourself, but he couldn't stop you, you had powers and he didn't. In a flash, you had left the house and continued to live elsewhere. A couple of years later, you were known as one of the worst villains of Kingsgate. You were caught by your brother whenever he started working as a detective, just to stop you.