Put your hands on her breasts.

You slide your hands around her waist, then up, until you are holding her bikini-clad breasts. They aren?t exceptionally large, but they are round and shapely. Rebecca gives a little murmur of approval, and wiggles a bit in your lap.

The fabric of her bikini is thin, and you?re easily able to find her nipples. You graze your fingertips over them, and Rebecca draws a sharp breath. As you continue to touch and tease, her nipples stand out and grow firm under your fingers.

Rebecca has stopped typing, and is steadying herself with her hands on your desk as she makes small rhythmic motions with her hips. ?That unties from your side,? she says quietly, and after a moment, you understand that she?s talking about her bikini top. You let go of her breasts, and she leans forward so that you can get at her bikini straps. You find it hard to concentrate on the knot, but after a little tugging and plucking, you pull the straps apart.

She lets go of your desk long enough to reach back, take your hands and place them back on her breasts. You feel goose pimples on her bare flesh, and the crinkles of her erect nipples, which you take between your thumbs and fingers. She groans this time as you play with her, giving a good, solid grind with her hips, and your cock is now growing dangerously overstimulated.