This interview with actor Mark Ruffalo will give you basically everything you need to know about Stan. He's a throwback, retro guy with a fauxhawk and glasses who just wants to chill with a beer and put on a Clash album. He's a simple guy.
But no, really, that's about all we know about Stan. He may not have the best work ethic in the world, what with all the drinking and smoking and mostly naked dancing on patients' beds, but he also doesn't seem like a bad dude.
We believe him when he says he didn't know the truth about Mary and Howard. He seems to genuinely care about Mary—he even supports her decision to leave Lacuna—and while he might bag on Patrick a bit much… it's Patrick, so we can't really blame him.
Stan's just another guy caught in the Lacuna web, doing his job (sort of) and trying not to worry too much about the ethics of it all. He's even responsible enough to call Howard when he can't figure out where Joel is, despite the fact he is naked and at least a little drunk and high.
As for the whole horn-honking thing, we'll let you decide whether he was being a good guy trying to help a brother out and save a marriage, or whether his attempt to conceal the kissing was just a low blow to poor Hollis.