Of course not!

"Okay, I think I need to take a break," he said. "My cock is too hard and sensitive."

"I guess so," said Mary reluctantly.

"No," Kaitlyn said. "That would interfere with your training."

"But Mistress, please?" he begged.

"You have to learn how to deal with being aroused while learning self-control," Kaitlyn explained.

"Yes, Mistress," he sighed resignedly.

Mary smiled and nodded.

"Okay," Kaitlyn continued. "If you can hold it for ten minutes, then you may take a break."

"Please, Mistress," he begged.

"I'm afraid that's all I can give you right now," she responded.

"Okay, Mistress," he nodded.

"Good boy," Mary praised. "Let's resume."

"If it's just ten minutes, he should be able to handle a little more," Kaitlyn added mischievously. "Mary, can you turn it up a notch?"

"Sure, let's see if he can take it," she agreed.

The ring began to vibrate more intensely.

George grunted. "Ugh! Oh, wow!"

"Are you okay?" Kaitlyn asked.

"Oh yes! Fuck, this is awesome!"

"Okay, we'll keep it at this level for now," Mary decided. "Ten minutes should be enough time."

"Great! And there should be a penalty to keep him motivated to hold out for the full ten minutes. George, if you cum before the ten minutes are up, I'm going to be riding you on the treadmill. With the cock leash still on."

"Shit!" he cried in dismay.

"It's all part of the punishment, right?" Mary asked.

"Yes, Mistress," he agreed.

"And once you finish the challenge, you will be allowed to cum. But only after I've given you permission."

"Okay, Mistress," he sighed.

A moment later, George was moaning as he struggled not to release.

"You can do it!" Kaitlyn encouraged him.

"Fuck!" he cried out in frustration. "Oh, shit!"

"You can do it!" Mary cheered.

"But I can't fucking stand it any longer!"

"Just five more minutes!"

Standing in front of him in her tiny miniskirt, she fingered herself a little. She knew it would be rough, but actually she was kind of curious to see him on the treadmill. It was going to be incredibly hot.

"Oh God," he groaned. "I can't take it anymore!"

"You can!" Mary insisted. "Go on!"

"Oh fuck!" he cried. "I'm gonna... I'm gonna..."

"Cum!" Mary declared.

His cock erupted as he shot his load onto the floor.

"Oh God!" he cried.

"There's still one minute left," Kaitlyn informed them.

"Ohh, sorry George," Mary apologized. "I was reading my watch wrong."

"No problem, my love," he smiled. Then he grimaced. He had been on the treadmill before.

"Get on the treadmill," Mary instructed George, carrying the lead of his cock leash over and hooking it onto the fitting.

"As you wish," he answered, shambling onto the treadmill in his ankle chains.

Mary set the ring on low. Kaitlyn also turned the treadmill on low and they set about getting him saddled while he walked.

"It's starting to get hot in here," Kaitlyn remarked.

"The ring is heating up," Mary confirmed. "It's supposed to help him keep himself under control."

"Doesn't it seem like it's making it hotter in here than usual?" Kaitlyn wondered.

"I think it's because I'm sweating," Mary chuckled.

"Well, let's make sure George doesn't sweat too much." Kaitlyn took off her shirt and threw it onto a chair. She was wearing a sports bra and running shorts.

"What are you doing?" Mary asked.

"Giving you an incentive to stay cool," Kaitlyn laughed.

"Oh, that's nice," she grinned, stripping off her blouse.

"Now George," Kaitlyn said, stepping up behind him. She cupped his balls in her hand. She removed his blinders, then pressed her erect nipple into his mouth.

"That's it," she told him. "Suck my titties."

"Okay," he agreed.

She started rubbing his nipples between her fingers and teasing his tongue with her nipple. She could feel his body start to tremble.

"Wow, that feels good," he sighed. He stumbled a little on the treadmill, causing the cock leash to squeeze his cock hard.

"See, George, I know you can do this," Kaitlyn reassured him. "You just have to try your best. Okay, let's get you saddled."

Both of them in their underwear now, Mary helped Kaitlyn get the gear on him. They clipped the nipple reins onto each nipple and fitted them into the saddle. Then they clipped one compressor over each of his balls, and fitted the pullstrings to the saddle. They untied his hands and pushed them up to a folded position horizontally in front of him, then attached the armbinder and connected it to the supports, making the handlebar. Finally, they removed his ankle cuffs, then Kaitlyn paused the treadmill for a moment while they got the ponyboots on him, then started it again.

The ponyboots had loops on them, and Kaitlyn was tempted to connect them with a chain, but she restrained herself. He had only been training for a few days, and it would be too much. Besides, she didn't have any chain lying around, anyway.

Once Kaitlyn had mounted him, sitting on his shoulders with her thighs clutched around his neck, she adjusted the settings, increasing the speed a little, but not too much. They'd have plenty of time to walk him through the routine. The ring was humming away on low, and she was pretty sure that it wouldn't go off until he finished the training session.

"Tell me what you're feeling, George," Kaitlyn asked.

"Oh, God, Mistress," he groaned. "I can't believe how good this feels."

"How does it feel?" she asked.

"It's so intense."

"Well, I think that's good," she suggested. "You need to be able to work yourself up without having to ask permission."

"Yes, Mistress," he agreed.

"I'm going to keep riding you, George."

"Okay, Mistress," he nodded.

"You can cum if you want, but the cock leash is staying on, and I'm not turning the treadmill off, so keep that in mind."

"Okay, Mistress."

"And remember, Mary will be in the audience wearing a bikini."

"Yeah, sure," he agreed.

"I'll be sitting near to the front so you can see me," Mary said. "If you don't race nicely, I will ride you on the treadmill."

"Oh no!" he cried. "Please don't!"

"Don't worry," Kaitlyn assured him. "I won't let you cum at the wrong time. You'll just have to follow my lead."

"Oh, thank you, Mistress," he moaned.

"Can you focus on what you're doing?" Kaitlyn asked. "Focus on your breathing and your muscles. Keep your eyes straight ahead."

"Okay, Mistress," he agreed.

"And remember, you can cum if you have to. The stimulation might get a bit overwhelming after if you do though."

"Okay, Mistress," he agreed.

She started to slowly increase the speed of the treadmill, keeping it just below a jog.

"Okay, George, listen carefully. If you start to feel like you're losing it, slow down a little. Remember, you don't have to obey me just because I'm your rider. In fact, I want you to disobey me sometimes, especially when you think it's appropriate. For example, if you find something else you like better than sucking my titties, I don't want you to stop. Do you understand?"

"Yes, Mistress," he replied.

"Good boy."

"Oh, shit!" he groaned. "This is a lot harder than I thought. My legs are shaking."

"This is actually not a bad racing pace. It's not too fast or too slow."

"Shit, I'm so horny!" he moaned. "Fuck, I can't take it any more."

"Like I said, you can cum whenever you need to," Kaityln reminded him.

"Oh, God!" he cried out. "I think I'm going to explode."

"Keep it together," she urged him. "You can do this!"

"Oh, shit, I can't!" he gasped. "I can't hold it anymore! I'm coming!"

Mary thoughtfully changed the ring to the maximum setting to give him a more intense orgasm.

He jerked and bucked against Kaitlyn's thighs as his cock exploded inside the ring, shooting its load onto her panties.

"Oh, shit!" he cried.

"That's it, George!" she encouraged him. "Give yourself a good fucking orgasm."

"Fuck!" he moaned. "Oh, fuck! I can't believe how good this feels."

"See?" Kaitlyn asked Mary. "It worked."

"Yeah," she agreed. "You did great. I think we should do this a couple times a week."

"N-no," protested George. "It's amazing, but it's too much! Please!"

Kaitlyn slowed the treadmill down to led him recover, but didn't stop it. After a minute or so, she felt he was ready to continue, so she turned up the speed again to a smidgeon below the earlier speed. Looking down, it seemed that the ring was still on an intense setting.

"I really don't think I can keep this up," he admitted.

"You could turn the ring's setting down a bit," Kaitlyn advised Mary. "But he's your fiancee, so it's your choice."

"Yeah, I guess," she agreed. "Maybe I should turn it down. This is a lot rougher than I expected."

"Okay," Kaitlyn told her. "Do whatever you think is best."

"Please, Mary," pleaded George.

Mary was fingering herself as she watched Kaitlyn ride her fiancee.

"Thank you, Mistress," he sighed, although Mary hadn't actually taken her advice yet.

Kaitlyn increased the speed back up to where it had been.

"Okay, George," she said, "you're going to have to pay attention to the ring now, but we can turn it down a notch if you need to. But remember, if you tell me to, I'll have to punish you."

"Oh, shit," he groaned.

Mary reached over and turned the ring down.

"Good idea, Mary," Kaitlyn told her. "Let's see what happens."

George suddenly gasped as he realized how much easier it was to keep his erection under control. He was still twitching, but the feeling got a bit more manageable, not that he was doing much managing, with his arms in the armbinder, his cock pulled along and squeezed by the leash, the treadmill forcing him forwards, and Kaitlyn riding him.

"Mistress," he gasped. "God, this is so good. But I don't know how much more I can take!"

"We'll see," his rider smiled at him. "Just keep working." He was working his way towards a third orgasm. He had discovered how difficult it was to continue after the second, though, so he looked like he was in no hurry for his third.

They continued for a few more minutes.

"Oh, shit!" he cried. "Oh, fuck!"

He came as hard as Kaitlyn had ever seen anyone cum before. He was shaking violently and squirting everywhere, although there was not that much cum this time. She kept her legs clamped tightly around his neck, and held him firmly in place. Every muscle in his body tensed and convulsed.

"Mistress!" he gasped. "Oh, fuck!"

"That's it, baby," Kaitlyn encouraged him. "Feel free to cum all over my clothes and my shoes."

"Yes, Mistress," he whimpered.

"Are you okay, George?" Mary asked.

"Oh, Mistress," he gasped. "I think I'm going to pass out."

"Well done, George," Kaitlyn told him. "Your first race on the treadmill has been very successful so far."

"Yes, Mistress," he sighed.

***

The ring was set at high intensity, but that wasn't a problem. George's cock seemed to be permanently enlarged, and even at reduced power, it was still straining the limits of the ring. Kaitlyn knew that it wouldn't last long.

She was sitting on his shoulders in the saddle, so she didn't have far to fall, but it still made her nervous. She didn't want to die by falling off of him before she'd gotten the chance to enjoy her life to the fullest. Fortunately, she didn't have to worry about that.

"Mistress," George gasped as he came for the fourth time that evening, "this is so fucking intense!"

"You earned it," Kaitlyn laughed.

"Is that it?" Mary asked. "It didn't seem to last very long."

"No, I'm afraid not," Kaitlyn told her. "The ring's just too powerful for him. We'll have to reduce the setting again soon."

Mary took her cell phone out of her pocket and snapped a picture of them. George was still in his ponyboy gear, although Kaitlyn had finally detached the cock leash from his cock and let him off the treadmill. They were wearing their gym clothes, but Kaitlyn didn't look too bad in her tight leggings and sports bra. George looked like he had fallen asleep standing up.

"Damn!" Mary snorted. "He looks like he's dead."

"I think he's worked hard enough for a nap," Kaitlyn noted. "I hope it doesn't bother you, but I promised George that I wouldn't let you ride him until he woke up."

"It shouldn't," Mary agreed. "It looks like you've got things well in hand."

"Yes, Mistress," he replied sleepily.

"Hmmm," Kaitlyn mused. "Now that I think about it, you're probably right."

"I wonder what George will think when he wakes up?" Mary asked me.

"I suspect he'll be a little disappointed that he didn't get to fuck me," Kaitlyn smiled.

Mary slapped his overabused cock. "I'm the one he's supposed to be fucking, we're getting married tomorrow morning, after all."

"Oh, right," Kaitlyn said. "Sorry."

"You two are awfully close," Mary observed. "You've spent every night together since you met. Are you sure I'm the one who's about to marry him?"

"I'm sure," Kaitlyn shrugged. "I just happen to like sleeping next to him."

"I see," Mary nodded. "But you know, I think it would be better if you gave him some space tonight. I don't think you should spend another night in his room."

"I think you're probably right," Kaitlyn agreed. "I'll go home after dinner. I don't want to intrude on your wedding either."

"That's fine, honey," Mary assured her. "Besides, I need my rest before tomorrow."

Mary handed Kaitlyn her towel.

"Thanks," she replied.

"I'd better get changed," Mary added. "I don't want to miss the ceremony."

"You know," Kaitlyn chuckled, "now that I think about it, I'm pretty glad that you're marrying him. I've been looking forward to spending the rest of my life with both of you."

"Me too," Mary smiled.

"So what do we do with him now?" Kaitlyn asked Mary.

"We might as well leave him tied up until morning," she suggested. "Then he can have an early breakfast with us and we can untie him. Then we can get ready for the ceremony."

"Sounds good to me," Kaitlyn agreed.

"I think I should put him back in his collar and leash while he sleeps," Mary decided.

"Okay, I guess," Kaitlyn shrugged.

"And I'll make sure he gets a nice shower," Mary added.

"Okay," Kaitlyn agreed. "I don't suppose he needs anything else?"

"No, I don't think so," she replied. "Unless you think he might need a sponge bath."

"Sponge baths are good for you," Kaitlyn pointed out.

"True," Mary agreed. "But I'd rather stick to showers. Anyway, I'll take care of him myself."

Kaitlyn stepped off his shoulders and removed his saddle, then headed towards the locker room.

"I'll call you later," Mary called to her.

"Sure," she waved, heading for the changing rooms.

After Kaitlyn had changed into her street clothes, she found her way back to the elevator. There was a note on the table with her phone. It read:

Dear Miss Kaitlyn,

Thank you for taking such good care of George tonight. I know that it must have been very hard work, but I am pleased that you were able to get him into such good shape.

Love, Mary

Kaitlyn opened the door to the apartment and went straight to bed. She fell asleep almost immediately.