Nope, can't hold back.

There is a line somewhere between ?It?s going to feel great when I come? and ?I absolutely have to come right now!? and you?ve crossed that line. You reach around her, cupping her breasts in your hands, pulling her body against you, thrusting your hips against yours. She makes a little surprised sound, then wraps her arms around yours and holds tight.

You buck, and push, and grunt, and if you could magically dissolve your pants with you mind and slip your cock into her, you would, but there?s no time for that, she?s straddling your thighs and riding in your lap and every time she bounces on you it just feels so, damn, good...

The first shock of your orgasm hits you, and if you wanted to be insider her before, you want it twice as much now. All you can do is hang onto her and pull her down against your cock as it releases itself in your pants. You gasp into her shoulder, riding out your own spasms, jerking and shivering.

When the fire in your blood cools at last, you have to blink a few times to get your eyes uncrossed. You slowly relax your hold on Rebecca. She pats you on the arm, glances over her shoulder and smirks at you. ?I don?t think that was as good for me as it was for you,? she says, ?but I?m sure you can make it up to me later.?