According to what I could find, they are sisters. If they are, it's an interesting scene. If you ignore that, it's a "meh" lesbian scene. Starts with ass-licking, some pussy-licking, anal fingering including three(!) fingers and ends with anal finger to mouth. Not much in the way of kissing or tit-sucking, which I think is a missed opportunity with sisters. Worth a look, if you're into this sort of thing, for the relative rarity if nothing else.

Trista Post real name is Bonnie Nejmanowski, and her sister Trinity Post's real name is Erin Elizabeth Cassidy (Source: IMDb). So I think they are half sister at best, its still dirty in a good way.

Funnily enough, this, hopefully, answers a question posed to myself yesterday, which is, are these two sisters? I'm guessing not.