New redpiller, working thru the sidebar reading so bear with me.

This girl that has a boyfriend seemed to show a lot of interest. She was holding eye contact more than other girls I talk to, enthusiastically carrying the conversation.

I don't want to make the mistake of assuming she's interested. I'll read up on IOIs but sustained eye contact seems to be a good indicator.

I am not exactly sure how to escalate without her throwing up the boyfriend shield. How do I fly under the radar?