Do 你 think Edward is a mardy bum? :)

Well of course he was. That is the way the character was written. He couldn't be all jolly about wanting to kill the girl now could he? So "Mardy" is a great description.

Yes, his character calls for a brooding, depressed individual. That is until he understands he can control his thirst for Bella's blood and returns back to Forks.