[tracilicious]

Honestly? I think you might be overreacting. Sexuality is a very normal part of being human. Even though legally he is still a minor, he already has adult sexual urges. I think by forbidding it you might add an element of shame that our culture could really do without.

I understand that you might like him to be more discreet. Though, in that situation I think I would want to do some soul searching as to what was making me uncomfortable. My kids coming into their own (no pun intended)? Shame my parents downloaded onto me? Concerns for safety/risk? Is it that he isn't married/my own views of how sex "should" be?

How would you feel about him having sex in your house if he were 20 and visiting home with his girlfriend? Why is it different because he is two years younger and living at home?

I think that Kevy was right in saying once sex has started it isn't going to stop. Taking an authoritarian stance and forbidding it is only going to promote sneaking around. I think I would want honest communication. Let him know that he isn't wrong, the desire for sex at his age is completely normal, and have an open talk about the risks and how best to avoid them.