I used to be that guy with crippling AA, but after some hark work and a lot of failures, I can go up to and approach any person in a social setting.

My SMV is fairly high for a uni student (trp mentality, tall, athletic, etc), but my next roadblock is how to advance from the initial introductory conversation to something that will lead to somewhere more interesting.

I've noticed recently that I'll for example start up a conversation and they'll be initially receptive while we exchange the usuals formalities but then the conversation will fizzle and there will no reason for me to be talking to her.

Spelling it out like this makes it seem like I need to initiate more sexually charged conversation. If so, how do I do that without coming across as creeping?

--edit--

the above post was written in the context of social events where alcohol is present if that matters