I know a man who has gone through his entire adult life never having a relationship. It isn't that he tries to go on dates with people and it doesn't work out. He never even tries to ever go on a date. He will only have sex with someone but he wants no other connection in any way. Not surprisingly, women don't like this(!). He seems to find normal social interactions almost painful.
He has a younger brother who couldn't be more different.
I've been wondering how common this sort of thing is? Do you know anyone like this?