Let's face it, Marius from Les Miserables is a bit of an
idiot.
He's been friends with Eponine since childhood, but
doesn't ever get the hint that she's in love with
him.
He's so shallow he falls in love with a girl after having
seen her once.
Eponine dresses as a boy to fight beside him but he
doesn't notice.
Eponine saves his life by taking a bullet for him and he
doesn't even realize it was her.
5 minutes after Eponine has died, he is singing about how much he
misses Cosette.