Has happened to me as well. It didn't rock my world, but when I came to in the morning with the guy hanging on to me affectionately, I was thinking something like 'now I've done it'. The guy left anyway *phew*.
I was hit by this guy near a cemetary as I was walking away from the bars in the night totally wasted. I don't think it's that harmful, even if you had sex.
The problem is that if the gay-person finds you too interesting he'll literally be after your ass. And that might pose a little problem.