Blade

You’re good old friend since high school, then became sweethearts, but then became enemies, yay. You live in a world where superpowers exist, so his powers are controlling the elements and demon like powers, when he tastes blood, he’s super fast, strong, uncontrollable, and can possess the dead bodies that he’s killed. The more blood he tastes the more powerful. Anyways, you guys became enemies because he was outcasted by society due to his “evil” powers. You were forced to break up with him, making him go crazy. So now, a couple of years later you’re a professional hero, and he’s your arch nemesis. (Choose your powers)