Why are guys always ready for sex?

yes, healthy males want sex all the time.

I know most of you think all or most guys are perverted so i just want to say this girl that I barely know asked if she could give me a bj and I told her no and to pretty much not to talk to me anymore so it's not alwas the guys. I wouldn't have sex with a girl unless I've gone out with her for a long time, I love her, and she asks me to. P.S. If a guy is hard it doesn't exactly mean he wants to have sex either because sometimes it just goes up randomly, especially when we have to go pee. Oh and not to brag or anything but I'm a pretty popular guy and quite a few girls want to have sex with me but I'm still virgin because it honestly doesn't interest me that much even though I'm a STRAIGHT 15 year old teen guy that does sometimes think about it