The Jem Bible
This book was written by Christy Marx in order for writers to get familiar with the series and keep the facts straight. (It didn't always work.) The Bible contains character profiles and other information.
In the profile for Phoebe Ashe (Rapture), it's mentioned that Phoebe spent most of her childhood living in San Francisco, California.
The Stingers Hit Town, Part 1
During the "Stingers Theme" video, Rapture and Minx are back-to-back at one point.
After Pizzazz leaves Riot's room, Rapture and Minx laugh, and Minx puts her hand on Rapture's back.
When Pizzazz wants to go home, Rapture puts her arm around Pizzazz and says "I'll come with you."
Near the end of the episode, during the "Perfect Match" video, Riot is singing to Jem about how they belong together. Rapture and Minx look at each other, touch the palms of their hands together, and sing "We're a perfect match, a perfect match."
"...a perfect match." "Together!"
There are several instances near the beginning of the episode where Rapture puts her hands on Pizzazz, like on her arm and shoulder.
In Part 1, Pizzazz tells Rapture and Minx, "There's a bunch of guest rooms on this floor. Take your pick." But in Part 2, after Pizzazz checks Riot's room and sees that he's gone, it looks as though she checks only one other room before saying "They're all gone!" So, Rapture and Minx probably shared a room. We don't see if there's one bed or two.
During the "Take It Or Leave It" video, when Minx and Rapture hug Riot, Rapture has her hand on Minx's hand.
A Change of Heart
At the Electronic Trade Show, Rapture puts her arm around Minx as they walk together.
Conclusion
While it's true that Rapture often hugs Riot, so does Minx, and the Jem Bible states that neither Rapture nor Minx have any romantic interest in Riot. They are touchy-feely with him, but it's a close friendship, nothing more.
I believe that Rapture and Minx are a couple and are perhaps sexually active. Would you like to comment on this section? Do you have any evidence to add? Then please e-mail me.