<human>: Can you provide a brief overview of the text?

We've known each other for about a month now, and as the title suggests she's 18 and I'm 19.

I'm serious about dating this girl but apparently she's holding out on someone else (this on-again, off-again girlfriend of hers). Someone who is COMPLETELY physical and emotionally unavailable. 

But as time goes on she seems to be coming onto me more and more... and as for someone who's very inexperienced sexually it's simultaneously intimidating and very difficult to say no.

We've talked about this a *lot,* too. She's very upfront- even going so far as to tell me that everything we're doing means absolutely nothing. 

She's clearly very attracted to me and I really like this girl, but... it feels wrong. We're simply using each other for the attention, and I'm afraid that, in the end, I'm just going to get hurt. At the same time, when it gets down to brass tacks I can't help but think with my dick.
<bot>: Exactly what the title says. I want to date this girl, she wants to fuck with no strings attached. The fuck do I do?