Spank her.

You step closer, your hand already raised. The first spank lands with a sharp crack, the sound echoing through the office. Her ass jiggles from the impact, a faint pink mark blooming on her skin. She gasps, her fingers gripping the edge of the desk, her body trembling. She’s already wet - you can see her body responding to the sting. Your hand comes down again, this time harder, the sound louder, the impact sending a ripple through her flesh. The pink mark darkens, spreading slightly as her skin reacts to the force. You focus on the same spot, your palm connecting with her ass over and over, each strike causing more and more pain as her ass becomes more and more tender.

A bruise is forming now, a dark, mottled mark where your palm has repeatedly connected with her flesh. She’s trembling, barely able to hold on to the edge of the desk, her body tensing with each strike. You don’t let up. Your hand comes down again and again, the sound of skin meeting skin filling the room. The bruise darkens further, a deep, purplish hue spreading across her ass. Her thighs are slick with her juices as you land blow after blow.

Her body is shaking now, her breath coming in short, sharp gasps as the pleasure and pain mix, sending her closer and closer to the edge. Finally, her body convulses - her back arching, her toes curling - as an orgasm crashes over her. She lets out a muffled cry as she rides out the waves of pleasure, her pussy clenching around nothing as she cums as it sprays all over your desk. You don’t stop spanking her, drawing out her orgasm, with each strike sending another jolt of pleasure through her trembling body until she collapses onto the desk, her body limp.

You step back and admire your handiwork, your cock already straining against your pants. She's an absolute mess, covered in sweat and fluids, heat radiating off her skin. The bruise on her ass is a deep, dark purple now, a perfect handprint marking her as yours.