Was walking through leicester square/china town sort of area a few years ago. I was somewhere between fairly well oiled and pretty damn pissed, after being in Ye Old Axe all evening.
Was approached by a woman who mentioned a similar prospect to the OPs, a line up of women drinks etc. She was skinny, twitchy, kinda bedraggled. On something I suspect. I asked where, and she started walking off expecting me to follow. I didn't intend to follow her and started walking off in the direction of my hotel.
Well, she turned around and started following me, screaming her head off, effing and blinding and causing a scene in front of the all the street drinkers. I carried on walking with her following, and she ran out of steam after a little while, but it was a worrying few moments for me as I had no idea whether it would escalate, or if some muscle would appear to help her out or what.
Its just a straight no thanks from me for any street approaches now.