Derrick and Kyle headed to the park, for sexercise, and possibly to sell some more straps. Kyle was cumming much too quickly than Derrick would have liked. She had spoiled him, letting him cum whenever he pleased. His body was hers to use and abuse, and she would make her toy know what it meant to be her slave.
She picked out a nice spot of grass and laid down, pulling Kyle on top of her with her straps after taking him out of his bag. "This would be a good spot for crunches", she thought.
"Tell me when you're about to cum, my bitch", she said, looking him in the eyes, "You will be punished if you tell me too late or if you don't tell me at all"
"Ok mistress. Are you going to turn me into your flesh dildo?", he asked with a tilt of his head.
"I am indeed, you're a smart little slut~", with that, she started her first set, pushing Kyle deeper inside of her as she rose up, and then pulling him out as she dropped down. He gave the signal on just the second rep.
"C- cumming mistress!", he groaned. Derrick quickly pulled him out with her straps, but to her disappointment, a torrent of cream splattered across her flat stomach.
"Perhaps we should take those straps off you for our first couple sessions", she said, as she brought Kyles face down to the mess he had made. He lapped it up as his ass was assaulted by straps, turning his behind red. After he had thoroughly licked Derrick clean his mistress took off his straps, temporarily putting them on herself for the moment. She moved her boy toy back into place and continued her workout. The two went like this for hours. Each time Kyle got better at lasting longer and giving the signal, but sometimes he purposefully messed up just to feel his goddess' straps against his slutty ass. He loved every second of it, anything with mistress was the best. It eventually got to the point where he was hardly even conscious, the only sensations being pleasure and pain, but that didn't matter to him, serving his mistress was his favorite thing to do.
Derrick carried the exhausted fuck toy home with his cock in her warm pussy. Despite her growing megalomania, she didn't have the heart to take him out of her. She periodically gave him a slap on the ass. Perhaps she would reward him with a bigger butt sometime later? The idea of playing with his nice plump ass was turning her on. She thrusted her meat dildo further inside her as she walked, moaning all the way home.