Prompt:

Now Mark wants to bring her Diaper to and beyond it's limits.

For that he prepares Sarah with an enema, but then rectally administers marshmallows. The sugar within them will stimulate the rectum, causing a huge urge after some time.

Also to ensure Sarah is unable to release through the tunnel plug immediately, he inserts a tampon into the tunnel plug, ensuring that a little bit of pressure builds up within Sarah, before that slides out and she involuntarily releases

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“I have an even more… creative way to really test your limits next time,” Mark said, a wicked grin spreading across his face.

Sarah’s curiosity was instantly piqued. “Oh? Do tell.”

“We’ll start with a small enema, just to make sure everything is clear,” Mark explained. “But then, instead of just letting nature take its course, I have a little surprise.” He produced a bag of colorful mini marshmallows.

Sarah’s eyebrows rose in amusement and intrigue. “Marshmallows?”

“Exactly,” Mark replied. “The sugar will stimulate your rectum, creating a powerful urge after a little while. It’ll be a slow burn, a delicious anticipation.”

Sarah’s eyes widened with excitement. “That sounds… wonderfully devious.”

“And to make sure you can’t just release everything immediately,” Mark continued, holding up a tampon, “I’ll insert this into your tunnel plug. It’ll create a bit of a temporary blockage, a buildup of pressure before it eventually… gives way.”

Sarah’s breath hitched. The thought of that delayed, involuntary release was incredibly arousing. “Mark, you’re a genius,” she said, her voice filled with anticipation.

The preparation for their next windy walk was filled with a sense of playful anticipation. Mark administered the small enema, followed by the surprisingly easy insertion of the mini marshmallows. Then, with a gentle touch, he placed the tampon into the tunnel plug.

Sarah then donned her extra-absorbent brief, the emerald green bodysuit, the wrist restraints, and the blindfold. The timed lock clicked into place, sealing her into her fate for their three-hour excursion.

As they walked along the windy coastline, Sarah felt a strange combination of emptiness and the subtle sweetness of the marshmallows within her. She could also feel the slight pressure from the tampon in the tunnel plug. The anticipation was building, a slow, simmering excitement.

About an hour into their walk, the sugar began to work its magic. A gentle gurgling in her stomach intensified into a powerful urge. Sarah squeezed Mark’s hand, a silent communication passing between them. She knew what was coming, and the knowledge that she couldn’t immediately release, thanks to the tampon, heightened the sensation.

The pressure began to build, a distinct feeling of fullness and the undeniable need to go. Sarah focused on the sound of the wind and the waves, trying to distract herself from the growing intensity. Suddenly, there was a slight shift, a moment of increased pressure, and then… the tampon was expelled.

The release was immediate and involuntary, a rush of warm, messy contents filling her brief. Sarah gasped, a mixture of surprise and intense arousal washing over her. She could feel the warmth and the texture against her skin, a stark reminder of her complete lack of control.

Mark squeezed her hand reassuringly. “Good girl,” he murmured in her ear. “Just let it all out.”

Throughout the rest of their walk, the effects of the marshmallows continued, leading to several more unpredictable releases into her already filling brief. The catheter continued to drain, adding to the overall volume and weight. The wind remained their faithful companion, whisking away any tell-tale signs.

Mark occasionally activated the vibrator, the unexpected pulses adding another layer of intense sensation to the already overwhelming experience. Sarah found herself completely lost in the moment, her senses heightened by the blindfold, her movements restricted by the restraints, and her bodily functions entirely beyond her control.

By the time they returned home, the three hours had passed. The weight within Sarah’s bodysuit was substantial, a testament to the extreme challenge Mark had devised. As he unlocked the zipper and removed the blindfold and restraints, Sarah felt a profound sense of satisfaction and a deep connection to Mark.

“That was… incredible,” she whispered, her cheeks flushed. “The marshmallows… the tampon… it was all so… intense.”

Mark smiled, his eyes filled with admiration. “You embraced it perfectly. You truly love pushing these boundaries, don’t you?”

Sarah nodded, a soft laugh escaping her lips. “With you, there’s nothing I wouldn’t try. You always find new and exciting ways to challenge me.” The combination of the sweet stimulation and the delayed release had created an experience that was both surprising and profoundly arousing, taking their play to a new level of intensity and surrender.