While this doesn't include a sex scene per se it is about two people first finding pleasure in pain that leads to a deeper relationship with more exploration to a D/s relationship. And it is a true story.
*
She can see her breath streaming into the cold air as she gazes out into the night sky. Basking in the sense of calm and peace suffusing through her body she listens to her breath as it slows back into a steady rhythm. She can feel the metal of the park bench beneath her shoulders, her hips and the soles of her knee high black boots. She slowly turns her head to gaze up into his black-rimmed green eyes. Seated back upon her hips, he was high above her. "That look," he says, disbelief in his voice.
"What look?" she replied with a lazy, cat-ate-the-cream smile.
"This look," he says as tightens his hold on her hair, pulling until her mouth and neck are exposed like an offering to him. She gasps in pain, in pleasure, the same.
His lips descend on hers, both mouths working, tongues twisting. He balls his other hand into her hair and pulls, making her moan into his mouth.
His other hand releases her hair to scratch his nails down her back leaving red marks behind, causing her arch her back in pleasure and make more noises that aren't quite smothered by his mouth on hers. Her body continues to move against his as he uses his nails to decorate her body with red trails, her back arching, muscles tightening.
"Oh yes," she moans as he digs his fingers into the sensitive flesh between neck and shoulder, already decorated with teeth marks. His fingers skillfully find that spot that turns pain into pleasure and quickens her breath into gasps, leaves her trying to keep her voice from echoing throughout the shadow filled park.
Suspended in pleasure her mind flashes back to the beginning, when she first asked in a whisper for him to use his nails and run them down her back. Shivering in pleasure she then asked for him to bite that oh so sensitive place between her shoulders and her neck. Knowing exactly what she wanted he held that sweet spot between his teeth, causing her to throw back her head in pleasure, and scramble her hands against the park bench trying to find something, anything to grab onto. "Enough," she gasped, "Enough."
She gave him a wicked smile. Intensely, a whisper as she caught her breath, she asked him, "Have you tried pulling my hair yet?" ....