Bareback Sex for Monagomous Guys

[nick]

My boyfriend and I have been dating for about 3 years now. We started having unprotected oral sex after we both went in for an HIV test about 2 years ago. We now want to start having anal sex unprotected as well. Aside from STDs, what are the other risks associated with bareback anal sex?

I choose to believe that I can trust my boyfriend not to cheat on me. He has proven himself so far and I don't think he'd be one to cheat.
Here are the specific questions I was wondering about.

1. What will happen to the semen after the top ejaculates? Can the semen itself hurt the bottom's ass? Does it drip out after sex is over?
2. Are there other diseases which are not sexually transmitted which can infect the penis from barebacking?

[marshlander]

If you are truly monogamous (not the vegetarians-who-eat-chicken kind of monogamous) and have tested clear of all disease just be sensible about cleanliness and the other normal stuff like not kissing or doing oral if you have a cold sore, for example. If you are unlucky you could catch a dose of NSU, but washing properly and peeing after sex seems to help keep things ticking over nicely. I am not in any way qualified to give medical advice, so you might want to do a bit of research into more authoritative sources of information.