Selfish superheroes seem like an oxymoron, but there are plenty of buff dudes in spandex in various fictional worlds who make saving people more about themselves than the people they're saving. Whether they're trying to impress a girl or achieve fame, sometimes a hero is saving others while only thinking about themselves. One has to then wonder if their motivations outweigh their actions - or does any of that really matter as long as people are getting rescued?
If every superhero was separated into the various Harry Potter houses, there would be plenty of DC and Marvel characters in Slytherin. This may come as a surprise, seeing as the Harry Potter books and movies paint every Slytherin as a one-note villain, but a smart Slytherin would understand that the best way to control others and stroke their ego would be to become a hero.