Why some guys won't put out?

I started hanging out with this guy and we've made out intensively a few times, but he pulls away and won't sleep with me. I've never experienced this before. I'm 26, people my age rarely JUST make out...why is he holding back?
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+1 y
Turns out, STD's CAN be a factor in not putting out.
Why some guys won't put out?
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