Hi guys. This is Kira here with character #2, Titus Summerby. A muggleborn and one of the many victims of the Muggleborn Registry, Titus is still trying to come to grips with the fact that his entire life was thrown off track almost immediately after he graduated. Even with nearly a decade behind him, he's still pretty damn effected by what he went through in Azkaban so much so that the two weeks he spent in the place when he was charged with the crimes of his oh-so-wonderful flatmate Andrew Gudgeon in 2003 was enough to break him all over again. He is, perhaps, the angriest little Hufflepuff, sort of a living embodiment of a badger, but his world-view has gone from being the open-hearted eager optimist that he was in school to a rather pessimist, resigned cynic who hates everyone and just assumes that world has it out for him in some way. Even if there's glimmers of the previous version of himself that come out often, especially when he has a particularly good day, and he definitely knows how to fake-it until you make it when it comes to being nice to people, whether he wants to be or not, he's still very obviously damaged to anyone who comes in contact with him for extended periods of time.
Also, unless you're Lydia, if you're a pureblood, he's probably going to assume the worst. Sorry about that.