If anybody think they know which movie this is, please let me know. I have a vague memory of watching it many years ago, but can't find the name of it anywhere to see it again.
Here's what I remember from the plot:
A pair of brothers are on a murder spree across the US. They break into homes where the families are (usually) away and lure both women and gay men back to these locations where they have parties/sex and then murder them.
One day they pick up 3 girls from a store and proceed to have the same routine. While the more submissive of the brothers takes the bodies of 2 of the girls to dispose of them, he expects to find the last girl dead when he returns, but she is still alive.
Somehow they find out that the girl is actually their step-sister (the same father that had been abusive to them had secretly had a separate family where he took care of this daughter).
At some point, she convinced the submissive brother to kill the dominant one. But in the end, she also murders him (turns out she was also a serial killer).
Not sure if she dies or not. Also, there are quite a few flashbacks to when the father was teaching them how to break into houses and kill people with just a belt.
Hope somebody recognizes the movie as I've been meaning to re-watch it for quite a while, but have been having 0 luck finding it.