Give him a sight worth wanking for.

You lean over, your eyes transfixed on his hard cock, seeing his hand gripping it firmly, sliding up and down in long slow strokes, the foreskin peeling back to reveal the enraged head, a small drop of precum already glistening around the tip.

With one hand on the floor for balance, with the other you undo the single button of your jacket, letting it drop open, knowing now he can look and clearly see your cream blouse, inside which your ample breasts are hanging heavy in your bra.

Reaching up, you feel the buttons of your blouse, finding that you did up to the top this morning, but quickly correct that by flicking the upper one open, then sliding your hand lower, you easily undo a second, knowing that in this position he will easily be able to see inside and so get a good view of your bra encased breasts.

Looking back under the desk you see your display is having its effect, as his hand has speeded up its travel up and down his cock, and the single drop of cum on the tip has become larger. Encouraged, you reach your hand down and pop a third button free, and as you do you feel the blouse fall open enough that you know he can see the full cups of your bra now.

Still looking under the desk you see he is certainly enjoying the view you are offering, and now feeling horny yourself, you slide your free hand inside your blouse, cupping one breast, feeling the weight of it hanging inside your bra, gently squeezing it and feeling your nipple stiffen and press against the soft material of the restraining garment.