Well, not that long, really - the strange feeling of having killed someone aside, that really wasn't your goal here. You cast your thoughts to the scraps of rubber. "Become Megan. Become Megan. Become Megan."
The rubber lifts up off the ground, reforming itself, stretching itself into a round form, its holes sealing themselves up. It grows, thickening at it grows, and before too long, it's taken on a vaguely humanoid shape, pink as before. That shape becomes more hourglass, as a face and something resembling hair form on top, two lovely tunnels on the bottom. The more complex, finer details form, and you realize you're not doing it, only feeding power to her. She smiles, looking at you with her empty pink eyes - soon she stops shifting, almost identical, as far as you can tell, to that girl who had you between her legs before, and you feel the connection break. She floats to the ceiling, giggling.
"That was AMAZING."
"I'm glad you liked it!" you shout up. "I almost left you for dead."
She waves dismissively. "You did not, silly."
"No, you're right," you lie, "I wouldn't do a thing like that."
She moves her head side to side against the ceiling, looking you over. "So this is what you look like?"
"Yeah! At least for now. I don't think I can go back to having flesh, but I have pretty good control. Why? You got a request? Get rid of the cock, maybe, or change the rest to match?" You smirk. "Or maybe you want one of your own?"
She giggles. "Silly - I like you just the way you are. Get up here and let's see what that thing can do."
You levitate up to the ceiling, cock first, steering yourself to hit home. The mucus and sweat of a short hour ago are gone forever, only a magical lubrication as your cock enters her rubber vagina, now with nothing at the end of it. You will your cock from your already generous 20 cm to twice that, her vagina stretching to match until it's nearly to where her spine would have been. You put a finger up her now immaculately clean ass, stretching her alimentary tract, now just a simple tube linking her ass and mouth, until you can stroke yourself from the inside. She returns the favor by putting her left arm up your ass, as deep as it will go, while massaging the outside with her foot.
You feel now that she's getting short shrift, so with your other hand you feel around her rubber vulva, feeling for places that might not be quite level, and begin stroking the tiny bump you find, while through her ass you reach the top of her vagina, still stretched over your cock, to find a latex assemblage connecting it to her waist, from which assemblage the protrusion at the front emanates.
Thus tangled up, you kiss, and become lost in the kiss, orgasming through every latex molecule in your body. You withdraw from the kiss, to see Megan smiling at you. You pull your hands out and take her in an embrace; she pulls her arm out of your ass and does the same. Staying inside her, the two of you remain there, embracing on the ceiling, for you can't say how long.