I'm not completely sure, but during high school I actually think I had my first serious sexual feelings for another guy.
We started talking to each other during some music lesson, all spontaneously, and I instantly thought "what a charming guy"; he was a hockey player, about 5'9 tall, and he had black, thick hair, tanned skin and tender eyes; I found him hot and cute.
He had a strict attitude, but it was blended together with his constant tender eyes and nice personality, so he came off as "cool" and cute at the same time.
Any way, whenever I got to spend some time with him I felt a strangely happy, exciting feeling, and I actually still just feel the urge to... hold him, or something.
I've never felt like this for a guy before, not even my best friends; we seemed to get along extremely well together, and it's very hard to explain, but I guess you get it by now.
Hm, post your views on the subject.