If you look into Stephanie's past is is likely she had an abusive/scary boyfriend situation.
Women like that look to "safe" guys who they aren't particularly into but who are providers and most of all, non-threatening.
In my experience those kinds of woman are always looking for the "real" relationship to come around. Ronnie likely picks up on this.
Liberman likely piqued her interest somehow by being less neanderthal in his outlook than Ronnie. She's likely starved for attention from a normal man.
When I was younger I had three different women attached to this sort of dipshit guy (my friends) come on to me when they were drunk at weddings. Obviously they're pent-up.
“When plunder becomes a way of life for a group of men in a society, over the course of time they create for themselves a legal system that authorizes it and a moral code that glorifies it." ~Frederic Bastiat