For me it's a huge turn-on when two actresses are already into each other in real life (whether friends with benefits or lovers) and you can clearly see that chemistry in their scenes together. A few great examples I can think of:
Allie Haze & London Keyes
Georgia Jones & Faye Reagan
Romi Rain & Abigail Mac
Any others?
Allie Haze & London Keyes

Georgia Jones & Faye Reagan
Romi Rain & Abigail Mac

Any others?