Niki stood in front of her mirror, her back turned towards the door as she tried to finish getting changed after her workout. She has just stepped out of her sweaty gym clothes and is now standing completely naked, reaching for a baggy sweater to put on. As she bent over to grab the sweater from the basket, her muscular rear flexed and her shorts dropped to the floor. She was unaware of the fact that the door had been slightly open and now stood there with her round, firm ass exposed and her large tits sway slightly as she moved.

She let out a little giggle as she straightened up and realized her mistake. "Oh fuck!" She cursed, reaching down to grab the shorts off the floor before quickly sliding them back on. Then she gave a playful smirk over her shoulder, not bothering to turn around. "Hey, don't look if it bothers you so much," she teased lightly, still completely naked apart from the sweater she'd just thrown on.

Whatever, you're such a baby, she thought to herself as she turned around fully, her large breasts swaying lightly again. "Fine," she said with a shrug, reaching behind her back and untying the sweater before letting it fall to the floor as well. She stepped out of her shorts and kicked them aside, standing completely naked in front of her stepbrother Jack once more. Her toned body was accentuated by her muscles and the shadows they cast on her skin; her large breasts pointed upwards while her flat stomach and wide hips made for an alluring silhouette. "There, is that better?" she asked teasingly, hands on her hips.

She smirked as she walked over to the bed and sat down next to him, resting her muscular thigh against his legs. "Come on," she said, "I'm only kidding. You know you don't have anything I haven't seen before." She reached out and pulled the pillow away from his face. "Besides, we're step-siblings; it's not like there's anything wrong with seeing each other naked, right?" He looked unconvinced but didn't say anything, so she leaned forward and gave him a quick peck on the cheek. "See? Nothing to be embarrassed about."

She let out a loud laugh as she straddled his body, her lower stomach resting against his chest. "And what do you think I am going to do now?" She teased, grinning wickedly as he squirmed beneath her. Placing one hand on each side of his head, she guided him closer to her pussy and gave another soft giggle when his breath began to caress the sensitive skin of her entrance. "Go ahead," she said with a mischievous grin, tilting her hips forward slightly. "Have a good sniff."

Her hips shifted restlessly, and she let out a soft moan as he began to lick her pussy slowly. "Mmm, that's it," she murmured, gripping the sheets beneath her hands tightly. Her thighs quivered with every touch of his tongue against her sensitive skin, sending waves of pleasure coursing through her body. She arched her back, giving him better access to her folds as he continued to explore and taste her. "Oh fuck," she breathed, unable to contain the growing need for release building inside of her.

"Harder," she whispered huskily, reaching down between their bodies to guide his head closer to her. Her fingers tangled in his hair as he obeyed, licking faster and more forcefully now, drawing out groans and gasps from deep within her throat. Her body tensed, her breasts rose and fell quickly with each ragged breath she took, their nipples hardening into tight peaks. "Yes," she moaned, "like that." Her hips bucked wildly against his face as the familiar tightness built up inside of her, growing ever tighter with every stroke of his tongue against her swollen clit. Finally, with a sharp cry of release, Niki came, her body shuddering violently as wave after wave of pleasure washed over her.

She collapsed forward onto Jack's chest, panting heavily as she tried to catch her breath. "Wow," she managed to gasp between breaths, "I didn't expect that would happen..." Her voice trailed off into a contented sigh as she wrapped her arms around him, feeling surprisingly close and connected to him at that moment despite their often-rocky relationship.

"Well, you didn't have to look," she pointed out with a smirk as she started to remove his clothes. "But since you did..." She trailed off suggestively, tossing aside his shirt and then unbuckling his belt. Her hands slid beneath the waistband of his pants, pushing them down over his hips and releasing his hard cock from its confines. Her palms cupped his shaft firmly, stroking him gently as she gazed down at his erection with hungry eyes. "Seems like you enjoyed it just fine," she added with a wicked grin.

She leaned forward and took the head of his cock into her mouth, sucking softly at first before deep-throating him and letting his length slide all the way down her throat. Her tongue swirled around the sensitive ridge beneath the tip, teasing it as she continued to bob her head up and down on his shaft. She looked up at him through narrowed eyes, panting heavily from the effort of taking every inch of him inside her mouth. "So tasty," she murmured before starting to suck harder, using one hand to stroke him in time with her movements.

Her free hand reached down between their bodies, finding his hard length and guiding it towards her entrance. She positioned his cock at her entrance slowly, taking deep breaths as she felt the familiar tightness of her body stretching to accommodate his size. Finally, with a hitch in her breath, she lowered herself down onto him, taking all eight inches inside her in one smooth motion.

"Oh fuck," she groaned, her eyes squeezing shut as their bodies connected fully. Her inner muscles gripped him tightly, milking his cock as he