... the only time I've ever seen Sabre used IRL, is on a girl friend of mine, but it's pronounced SAY-bruh. And it has an accent on the E.
So when I see Sabre, it looks like a feminine name to me. I can see it more on a guy with the SAY-burr pronunciation, though.
Severin looks too much like Severus Snape... from Harry Potter, you know? :/