When I was young I had two cousins and their room sometimes stank of spunk, I didn't recognise it at the time but I kinda likes the smell. When I went to uni, I'd not done anything with a boy before, but was in a housemate's room and recognised the smell. I don't think mine smells, but this was really distinct.
I had only been with girls, and kind of knew what I was by then, but was in denial. I ended up going our of my way to smell his clothes when I was in his room. It was a shared house with 3 other lads, and it all escalated to me sneaking into rooms and seeking out what they had used to wipe up their play sessions. I was even stripping off and wanking in their beds with their grotty cum smelling items.
One of them used to regularly masturbate in bed, probably in the morning, and mop it up with his pants, which were kicked off at the bottom of the bed. I think it was in the morning because I've found them still wet before. I'd either jerk off with them clutched to my face, or ejaculate into them.
I know this is pretty shitty and I regret it. But this is what turned me into what I am today and made me realise I prefer guys.