Yes, some do. It's just for looks though. I'd recommend against it though because girls don't expect it, and you'd be very itchy a few days after when the new hairs come in.
with a razor
No. Most men shave, gay or straight.
Yes girls love a guy with a shave area
It reduces the drag of his or her, guys shave too, legs or arms
Yes if he wants to, nowadays it is seen as the norm for guys to trim or shave their pubes.
Not necessary. Some swimmers shave their legs and entire body for less resistance in the water.
Because it looks ridiculous on a guy.
Some do, most don't.
There's somthing wrong with the guy if he doesn't......
There is no should or shouldn't, it is a matter of personal choice, some guys do and some guys don't.
Yes, anywhere from a nice trim to completely bald.
No, not at all. It is only gay if you are sexually attracted to other guys.