Mosel Sex slave 07

When she came back half an hour later, Diana was wet with perspiration and looking totally worn out." She is doing better than I was the first time, mistress." Marg kissed both of them smiling at Diana.

"Do you think you can give your master a little surprise tomorrow night?"

"Oh mistress I'm not very good at this but I will work hard every day so you will be pleased with me."

"I know you will, now I want Lee to have intercourse with you. Lee slipped the dildo out of her vagina and pulled it out of Diana. She then got up on her knees between Diana's legs. Marg picked out a strap-on dildo and fitted it on Lee. She took a hold of the imitation penis and with Lee leaning over Diana, carefully fitted it into her vagina. Once she got it inserted, Lee lowered her lithe body on Diana and began to stroke her slowly. Diana reached her arms around her sex slave sister and responded, trusting her vagina on to the intruding penis. Her mistress gripped each of her legs, wrapped them around Lee's body, and told them to french kiss. The penis had a whistle on it and Marg told her that she wanted to hear it. When it blew, Lee pulled it out and then back in slowly. Diana soon realized that if she wanted to be stroked faster she had to squeeze it quicker. She began to moan, clutching Lee's body with her hands and thighs. Her moans became panting screams, as her juices began to flow and then moans as she savored her orgasm. Lee then pulled out the penis and moved down to lick the juices of her vagina. The mistress removed the strap-on and they were then told to change places. Marg strapped a larger penis on Diana. She helped Diana guide the member into Lee's throbbing hole.

As soon as Diana penetrated her vagina, Lee made the Whistle blow three times, before Diana could even get time to react. Her short little legs clamped around Diana and her arms forced Diana entire weight onto her small body. Diana tried to take some weight of her with her hands but Lee pushed her hands out of the way showing them on her buns. Lee murmured into her open mouth to go faster and faster. Diana pumped her hips up and down trusting the penis into Lee's little body as the whistle blew two or three times with each stroke. Lee came, shaking uncontrollably, sucking on Diana's mouth, and digging her fingernails into her back. When she eased off, Diana moved down and licked her vagina, sucking the delicious juices. Marg removed the harness and inserted the wet dildo into Lee's mouth, letting her savor her own flavors of the dildo. 

The girls then sat up on the table, with their legs over the side. Marg put her arms around both of them, kissing her devoted sex slaves. "Every day now, you will make sure that Diana does her exercises, Lee. Of course, it will be difficult for you two, not to turn it into sexual intercourse. So I might let you have an orgasms once a day when I'm not here, but you must call me first and get permission." The girls cooed and kissed her, one on the mouth and the other on the neck and then the other way around. "I got do some work at the desk; clean up here and then show Diana the 'female on top' drill in the gym. 

Lee showed Diana how to clean the dildo's they had been using at a sink in the corner of the room. Diana dried them and they put them in their proper place. They closed the door to the special room and Lee showed her the hidden lever that opened the door. 

"Now Diana for your next exercise; get down on this mat on your knee's. Rest on your elbows and spread your thighs out wide. That's good, your stomach should be off the floor." Lee got down next to her, in the same position. She then started to move her rear end up and down rapidly. Diana imitated her, keeping up the same pace. They kept it up for a few minutes until Lee slowed down and rolled over on her side exhausted. Diana stopped as well, smiling at her sister. "Lee took a few deep breaths and laughed, "You are not tired out are you?"

"No I stopped because you did, wasn't I supposed to stop?" Diana continued, bouncing her rear end again.

"Looks liked she's got you beat there, Lee." Marg had been watching from her desk. "Don did say that Diana has a very strong build." Lee started again, trying to keep up with Diana. After a few more minutes they both stopped, stretching their bodies out on the mat. "Tell Diana what that exercise is for Lee." Diana looked at Lee, waiting.

"Don't you know, sister?" Diana shook head, her eyes widening. "It's for having sex with a man, when you're on top."