Take it real slow.

You return about five hours later. The room is silent except for the faint, maddening hum of the vibrator as you push the door open. The scent of her arousal hits your nostrils like a punch, overwhelming your senses. Gemma is a complete mess, her skin glows flushed pink, glistening with sweat, and her lips are swollen from biting back moans. Her wrists are raw from tugging against the restraints, and her thighs tremble as she tries to lift her hips one last time towards the cruel pendulum of denial, but she is defeated by complete exhaustion.

"No more cumming for you," you say, as you press a finger against her clit and her body tenses, her muscles seizing up as she teeters on the edge.

You forbid Gemma from doing anything sexual - even masturbation - for the next few months, and untie her from the bed. She looks at you with longing eyes, but obeys you unquestioningly, her body shaking as she cleans herself up.

True to her word, she stops. After a month of complete abstinence, you let her know that she can watch porn again. However, she can only watch it while you’re there, and she’s not allowed to touch herself. So, every night for an entire month, you sit on the couch and jerk off to porn while she watches you, frustratedly fidgeting with arousal. Of course, you let her clean up your cum with her mouth once you’ve ejaculated, but that’s the extent of what she’s allowed to do.

From then on, she's a bundle of nerves, her wants and needs unfulfilled. It gets to the point where she is in an almost constant state of arousal. She carries several dozen pairs of clean panties in her handbag, as she is always soaked within half an hour and needs to change them. She’s practically in tears when she’s forced to watch you masturbate, and hungrily catches your cum in her mouth when you climax.