I agree with the personal approach. If he hasn't come out with sexuallity, which he has no obligation to do so in a work place, since heterosexuality is assumed for a male, unless you're overly feminine, in which homosexuality is implied...it would probably mortify him for anyone to know. Maybe he's not homosexual, maybe just curious about the same sex. When I make a decision, I try to look at things from the other person's perspective to the best of my ability. I had a job once working in a car dealership, in a community of snobbish people, and it made working there uncomfortable. I liked the money, and the job, but it was awkward. I ended up quitting, I dreaded having to go to work everyday and be looked upon differently, in that case for no reason except for that I wasn't the richest girl and I was working in a wealthy community.

If you feel obligated to report him, is there any way that you don't have to show the exact sites to which he went to?