Being a hero is fairly easy but he wears a black cape and glowers at people so no one finds out. At night he swaps sides and wears a different black cape and doesn't scowl at everyone.
Villainy, he finds, is a lot easier than heroics and not just because he was expected to hide. Severus liked hiding.
Sometimes he feels like he should draw up a chart of his personas just to find out how much he was acting in each role.
Sometimes he wonders which role he likes most; the hero or the villain.
He'll give you a hint:
It's the one he acts the least in.