Ok, so me and my bestfriend are both 17 year olds and are quite into girls, i've been bestfriends with this guy for 5 years and ever since we first met we've become closer friends with every time we've seen eachother. He's really helped me out a lot with all the issues I've ever come across, he has helped me become so much more self-confident and we can both tell eachother ANYTHING. So he tends to end up falling asleep at my house a lot when it gets late and we are playing the xbox or watching a film. And a couple of days ago, he fell asleep and I just carried on watching the film as usual (it gets a bit weird around here, so if you're not great around homosexual materials please stop reading at this point. Lol). I was watching a horror film and it happened to get to the usual sex scene, and it got me slightly horny; I stayed this way throughout the rest of the film. As the credits came on I looked at my bestfriend then my imagination became a little experimental and I imagined myself having gay sex with him (just to make sure I HAVE NEVER had gay thoughts before, even when I think of any other guy in that way other than him, it makes me feel really uncomfortable, just as it would a for any other straight guy) and for some reason I really didn't mind, in fact it turned me on a bit and ever since then I keep fantasizing about him. One big problem is that his parents raised him to be slightly homophobic, it's not that he hates gays, it's just that unless he's like me, I think telling him what i've been feeling recently would, at the least, creep him out of the friendship which I treasure soo much. Someone please tell me whether this is becoming bisexual all of a sudden, or if it's just human nature not being used to such a close friendship or whatever, and if I am Bi, what I should do about it? Should I tell him? Thanks for reading all that and please try and give me helpful and mature advice :)!.