She has no other choice

"Can I have a pen." Diane says meekly.

You hand her one and she uses it to timidly sign her name to the contract, securing her new position at your company as a mindless sex ****. Whilst you couldn't be happier, Diane looks the complete opposite. She sits there in silence, likely pondering how exactly her terrible decisions in life have led her to this moment.

"Why are you doing this to me?" She asks, appearing to be on the verge of tears almost.

"You tried to manipulate me into cleaning up your mess by seducing me with your body. This is all to show you how misguided you were. You tried to control me so now I'm controlling you instead. Don't think of it as a punishment, think of it as a chance to show the world what you really are, a MILF so **** to have her holes stuffed that she becomes nothing nothing more than a cocksleeve to be used to drain men of their cum."

Diane sits there a moment staring at you, pondering what you've just said. You can see the cogwheels turning in her mind as she tries to determine if that really is the truth about her.

"Why don't you bend over the desk so we can commemorate this momentous occasion." You say, standing and walking round to Diane.

This snaps her out of her mental descent. In line with her contract, she does as she's told and rises from her chair to bend over on your study desk. You're soon inside her, pounding her pussy from behind as her body slides back and forth on the desk. Her head rests right next to the contract she's just signed, giving away most of her rights to your company.

As you roughly fuck her from the back, you grab her by the hair and lift her head so she's looking right at the contract she's signed.

"Why don't you sign it with those pretty lips of yours too." You say, pausing a moment from your thrusting to allow her to do as you say without being moved around too much.

Diane does as you say and presses her mouth to the paper right next to where she signed, leaving the imprint of her plump, cock-sucking lips thanks to the bright red lipstick she's wearing.