This is written for the LWS Trope Bingo Challenge on Tumblr.

Bingo Card Number: 2

Trope: Gender Change

Many thanks to my beta reader Black Angel of the Underworld.

Basically a shameless PWP.

Sharon Holmes painted a tantalizing image amidst the mass of writhing bodies on the dance floor.

John kept his gaze on her while the pounding beat of the club's music reverberated in his ears.

She was slim and pale with dark hair, her pale blue eyes locked hazily onto John as she danced. Her tight black dress hugged her every curve, the leathery material clung to her hips and thighs, reflecting the flashing lights as she moved lazily to the beat.

John's mouth went dry as he watched her. He wanted to touch her. He wanted to take away the groping hands on his girlfriend. She was his, damn it. But he couldn't.

And it was plain torture, to just sit there and not able to do anything when Sharon was being so irresistible right in front of him.

Damn the case to hell.

He swallowed thickly, fingers hovering above his bottle of beer before taking a large swig.

When he met her gaze again, she smirked, her perfect cupid's bow quirked in a sensual manner that said she knew what effect she had on him.

She gave him a wink before slapping away the hands that were reaching towards her, and walked gracefully towards him.

"Well, darling," she drawled beside his ear. "Having fun?"

Her smirked deepened when John just grumbled in return. This woman was going to be the death of him.

"Problem?"

"No." John cleared his throat and hoped it would be enough to clear his brain of any pornographic images of her gyrating against him. "The suspect?"

"Not him."

"You sure?"

She rolled her eyes at him. "Don't be obtuse, John. Of course I'm sure."

"Well…"

She grabbed his hand before it had a chance to wrap around her hips, and blew his reddening ear. "Let's go home."

And soon as the door was closed, his lips were on hers, hot and desperate.

John quickly wrapped his hands around her waist possessively as he led them into the living room, all the while keeping his lips on hers.

Her lips tugged on his bottom lip, giving it a non-too-gentle nip before sucking it into her warm mouth and soothing it with her hot tongue. John moaned into his partner's mouth, his body feeling all too hot as blood rushed down south, causing his erection to strain further against the confine of his trousers.

The hands Sharon used to grip at his shoulders slid upwards until they tugged at his blonde hair. Her nails scratched at his scalp lightly, something she'd discovered John liked after their first kiss all those months ago.

John pulled her tighter against him; the pressure of her breasts against him made him groan into their kiss before the need to breathe became too strong.

He leaned forward to press their foreheads together, breathing in each other's breaths. His voice was hoarse with lust when he whispered, "Want you."

Sharon pressed another kiss to his lips before moving her hands down his torso, easily finding his hard and pulsing length. She felt him gasp against her throat as she continued stroking his cock through his trousers, teasing the length with a hard grip once in a while.

John nipped the place below her ear, knowing it to be one of her sensitive spots, before moving down to her chest; his wet tongue darted out and licked one pebbled nipple that was visible through the thin layer of her dress before sucking it hard.

She tilted his head upwards and licked his swollen lips before pushing the ex-army doctor to his armchair. "Sit down, John."

"Wh – What?"

She leaned forward and blew his ear, causing a shiver down his spine. "I want you to watch me."

Moving to her armchair, Sharon slid down in her seat and spread her legs, giving her flatmate a clear view of her wet knickers.

"And don't touch yourself." She licked her lips at John seductively, which elicited a pained groan from him before pushing her dress up and dipping her one hand into the damp warmth of her lacy, see-through knickers. She kept her eyes on her flatmate when her fingers played delicately along her slippery folds, and she propped her legs on the sides of the armchair to slide a finger inside herself.

"Fuck." John pressed his legs together in the hope that he could touch himself as the slightly damp surface of his boxer rubbed against his sensitive length.

Sharon smirked to herself at the sound of John's breathless curse, knowing how bothered the doctor was. Oh, how she loved to torture him.

Keeping a finger inside herself, Sharon used her other hand to take her knickers off, keeping her movement as languid as possible, all the while keeping her eyes on John.

His breath hitched when the knickers were fully removed as she inserted another finger inside her. He wanted to touch her; oh God, he wanted to touch her so badly. John swallowed hard as his head thumped against the back of his chair and closed his eyes while trying to find a reason to not just reach across and take her right there.

"Please, Sharon."

Sharon darted a look at the doctor and saw his eyes closed in agony. "Eyes on me, John."

When his eyes opened, Sharon moved her fingers to tease her clit; her legs shook a little when she rubbed the wetness around, before returning them to her entrance.

"That's right." She gave him a seductive smile before thrusting the two fingers in and out, angling her arm so her thumb could rub at her sensitive clitoris at the same time.

Still rubbing, she reached up with another hand to tug her dress down, exposing her right breast. She sucked on her thumb before using it to massage her nipple to full hardness, then did the same to her other breast.

Soon, the living room was filled with the sound of harsh breathing and wet, rhythmic squelching.

"Oh!" She couldn't help but moan when her movement became frantic, bringing herself closer and closer to the edge.

All too soon, she arched her back; the orgasm swept through her in a powerful wave of pleasure, leaving her shaking and gasping in her armchair.

"Oh God, Sharon." John's cock was throbbing so hard in his trouser that he had to press the heel of his hand against his crotch to relieve some of the pressure when it became too much.

In the afterglow, Sharon had her head thrown back against the seat, her body covered in a light sheen of sweat, and her dark curls plastered to the side of her sweaty face.

John had never seen anything sexier.

"Now." She glanced across at him and smirked at the obvious bulge in his trouser. "Need a hand with that, doctor?"