The afterlife has its downsides, but the sex isn't one of them. River can go anywhere now. River can do anything, and anyone, and best of all, she can do it whenever she wants. When she gets tired of exploring the infinite landscape of Charlotte's imagination, she can beam herself out through the universe. The Doctor always takes her calls these days, and so does the sovereign of Starship UK, which is still wandering through space.
Which is how she ends up with her head between Liz X's thighs at the same time that she's riding the Doctor with abandon. It's an interesting experience to say the least. All of her previous experiences with more than one person at once involved all interested parties in the same room. This time, it's simultaneous, as out-of-body as a data ghost can be considered to be, given that she hasn't got an actual body anymore. At least her projection or what have you is solid enough to touch, and oh, touch she does. At the same time she's kissing the Doctor frantically, grinding her hips down against his, and lapping at Liz X's clit, relishing each moan. Liz has her hand possessively on River's head; the Doctor looks up at her with wide worshipful eyes.
River grins, breathing hard. Oh, this is new, this is different, and she likes it very much. Everything's happening all at once and it's perfect. The Doctor's fingers dig into her hips. Liz tugs gently at her hair. The Doctor moves in her, panting, and River flicks her tongue hard over Liz's clit until Liz is moaning in one unbroken stream of guttural sound that echoes in the space between River's thighs. She bears down on the Doctor until their bones nearly notch together. She slips three fingers inside Liz and groans against Liz's skin at how tight and hot and wet Liz is around her. Liz groans too, her fingers fisting around River's hair. The Doctor reaches for her clit. His fingers know her, play her like a familiar melody, hit all the right notes in perfect time as her tongue echoes the rhythm of it against Liz's clit. The Doctor thrusts into her, his face tight with longing. River gasps and shivers, and she's still shivering between Liz's knees.
"What's wrong?" Liz asks, her voice husky but concerned.
"I'm coming," River manages to say, and then the full impact hits her.
"Oh, River," the Doctor gasps, his hand coming up to cup her cheek.
Her muscles spasm and she's almost flung flat, her mouth open against Liz's thigh. She recovers herself as the Doctor strokes her back, and she sucks hard at Liz's clit. Liz cries out, tugging at River's hair, but the pain feels good. The Doctor isn't quite finished. She urges him on, yielding her body to his use. River's more than a little occupied with coaxing Liz from a moan to a scream; she uses her teeth and her fingers, and her other hand reaches up to find Liz's nipples, stroking and pinching. Liz makes a satisfied noise that quickly turns into something much louder and higher. The Doctor bucks up into her, and it's all River can do to balance over him as his lean body jolts.
And then Liz is coming, her hips jolting against River's lips as River holds her down, pulling hard on River's hair and the pain is like a jolt of electricity. And then the Doctor is coming, his forehead pressed against River's breastbone, half-gasping and half-kissing, his lips fumbling against her skin but his cock unerring, finding the right spot somehow so that River is coming, oh, she's coming apart, caught between the Doctor's hips and Liz's, right where she wants to be, collapsed on the Doctor's chest, her head pillowed on Liz's belly.
"Oh god yes," says River in both places. The Doctor laughs, incredulous and wondering. Liz just smirks.