In canon, he's... bipolar, maybe? He has both manic and depressive phases, and craves mental stimulation, otherwise he mentally caves in on himself: the cocaine habit is how he self-medicates between cases. (You see a bit of that driving need for mental stimulation in Elementary when Miller!Holmes is hatching the police scanner, quivering for a case.) There's an argument to be made that canon!Holmes is perhaps on the spectrum, too -- the way he catalogs all particulars, never generalizing -- but I don't really see any other parts of the spectrum's suite of behaviors in him.
Canon Holmes has a tendency to run roughshod over Victorian mores, and he's as rude as fuck about what people fail to observe/deduce, especially the Scotland Yard inspectors. Beyond that, though, he's not actually an asshole. (Well, things like The Dying Detective aside. His relationship with Watson is all fracked to hell and back, IJS.) He tends to be consistently solicitous of clients' pain, for example, and will go out of his way to not embarrass them. He does have the geek-boy thing where The Internal Logic of Being Right >> Social Convention, but he doesn't view that as a reason to eschew manners. (Again, with exceptions.)
Re: My dear Watson, I owe you a thousand apologies!
Canon Holmes has a tendency to run roughshod over Victorian mores, and he's as rude as fuck about what people fail to observe/deduce, especially the Scotland Yard inspectors. Beyond that, though, he's not actually an asshole. (Well, things like The Dying Detective aside. His relationship with Watson is all fracked to hell and back, IJS.) He tends to be consistently solicitous of clients' pain, for example, and will go out of his way to not embarrass them. He does have the geek-boy thing where The Internal Logic of Being Right >> Social Convention, but he doesn't view that as a reason to eschew manners. (Again, with exceptions.)