But these words people threw around—humans, monsters, heroes, villains—to Victor it was all just a matter of semantics. Someone could call themselves a hero and still walk around killing dozens. Someone else could be labeled a villain for trying to stop them. Plenty of humans were monstrous, and plenty of monsters knew how to play at being human.

Vicious by V.E. Schwab (emphasis mine)

Just... this quote gets me EVERY. TIME. Especially the line I bolded, but I felt the need to grab some of the surrounding context. It's so amazing and I stan Victoria so hard.