I'm an otherwise straight man, and I don't even look at guys. But for some reason, I don't mind sucking a cock on occasion. It's only the cock that I'm interested in - for pretty much the same reasons given in this thread: I like the pulsing and the power of bringing someone off. It's the same reason I like eating pussy. But the thought of any other form of intimacy with a man is actually revulsive to me. It's a very interesting development for me. There's only one guy that I suck off every now and then. The rest of the time, I'm only interested in the ladies.