Maybe it's your approach? Maybe he felt as though you were
harassing him or something?
My answer would be to just forget about this guy. If he says that
he doesn't want you, then so be it: he doesn't want you. You have
to respect his decision and move on.
I'm 23 years old, by the way. I've been rejected by a total of
three girls so far. Each time it happened, I decided to respect
their decision and move on. It was like a punch in the gut when
they rejected me, and it was an even harder punch when they all got
attached to other guys later. But I've learnt to accept their
decisions and carry on with my life. If they can carry on with
their lives, then so can I.
Also, as you said, he values sex more than relationships. In other
words, even if you do get into a relationship with this guy, he's
more likely to use you for his own entertainment, namely, sex. He
sees women as nothing more than objects for his own pleasure.
Why do you still want to be with such a jerk, anyway? He is a
disgrace to us guys and a bane to you women. I say forget about the
jerk and find another guy who'll treat you better.