Riff Raff and Magenta, of course.
Why was Riff Raff so mad at Frank at the end? I never understood that. They were all from the Transylvanian planet in the Transexual Galaxy or whatever, and the partygoers (who I always took to be upper-ups checking on Frank's research) seemed pretty cool with everything Frank was up to, so how bad could Frank's behavior possibly be?
Well, I guess Frank was kind of a jerk to Riff Raff. Maybe RR was just jealous. Magenta was always pretty indifferent.
I'm going with jealousy. Sorry, Riff; you can't compete with a Charles Atlas man.