Mistress has got you into the same room as her other slave which can only mean one thing. You're having a bisexual threesome and it's going to be awesome.
I know that you've always secretly loved the idea of having sex with another man while I'm in the room. Your eyes always light up whenever you see another male slave that is devoted to me. Well today, I thought it would be a great idea for us to live out those fantasies. See, I'm in the mood for some hot bisexual action and it just so happens you are too.
Suck his cock for me and see how much he likes it. Oh, that's perfect - you really do know a thing or two about giving a hot blowjob, don't you? Now I'm going to let one of you fuck me, but before that happens, you've got to take the other's guy's dick in your asshole. You want to go first, right? Good - get on all fours and prepare yourself for a bisexual ass fucking that's out of this world.