The Dirtiest Thing I Have Ever Done

The dirtiest thing I have made a woman do I put on my little sisters underwear and bras and her dresses and fuxk her in them and made her call me big brother

“She’s gone, you know,” Kai’s voice was a low hum against Lizzie’s ear, the phone still pressed to his head, a faint buzz from the dial tone confirming his sister’s successful departure. “Bible camp. Two weeks of purity and prayer, far away from all this.” He gestured vaguely around his living room, a chaotic landscape of discarded snack wrappers and forgotten video game controllers.
Lizzie’s dark eyes, framed by impossibly long lashes, met his from across the room, a slow, knowing smile spreading across her lips. “Oh, really? And what’s ‘all this,’ exactly, Kai?” She leaned back into the plush cushions of the sofa, her black tank top clinging to the curves of her chest, a stark contrast to the innocent scene he’d just described. Her painted lips, a deep, glossy red, puckered slightly.
“Chaos. Freedom. Opportunity,” he listed, his own smile widening. He tossed the phone onto a pile of magazines, the dull thud barely audible. “My parents dropped her off an hour ago. They’re driving to Grandma’s for the weekend, ‘to decompress from the stresses of sending their little angel off to find God.’” He mimicked his mother’s saccharine tone, rolling his eyes dramatically. “Translation: I’m home alone until Sunday night.”
Lizzie pushed herself up, a graceful, fluid movement. She moved towards him, her hips swaying subtly. “Home alone, huh? Sounds like a party.” Her voice was soft, husky, a challenge wrapped in silk. She stopped just inches from him, her scent, a mix of something sweet and something musky, filling his senses.
“Oh, it’s going to be a party, alright,” he breathed, his gaze dropping to her mouth, then lower, to the swell of her chest. “But not the kind with loud music and cheap beer. This is… a different kind of party.” He reached out, his fingers brushing against her arm, a spark igniting between their skin.
She leaned into his touch, her eyes sparkling with an unreadable mischief. “Intriguing. Tell me more, Kai. What kind of party do you have in mind?”
He took a step back, a playful glint in his eyes. “It involves a little… role-playing. A secret. Something we’ve never done before.” He watched her carefully, gauging her reaction. Lizzie was always up for anything, but this… this was different. This was pushing boundaries he hadn’t dared to consider until now.
Her eyebrows arched, a subtle invitation. “Role-playing? I’m listening.”
“It’s about Emma.” He saw a flicker of surprise in her expression, quickly replaced by curiosity. “Not… not *with* Emma, obviously. She’s off communing with the Lord.” He chuckled, a dark, conspiratorial sound. “But… about her. Her things.”
Lizzie’s smile faltered, just for a second, a tiny crack in her confident facade. “Her things? What are you talking about, Kai?” Her voice held a note of genuine confusion now.
He took her hand, his thumb tracing circles on her palm. “Come with me.” He led her out of the living room, past the kitchen, and down the short hallway to the bedrooms. He stopped in front of a door painted a pale lavender, adorned with a faded poster of a unicorn. He pushed it open slowly, revealing a room that was a stark contrast to his own organized chaos. Emma’s room was meticulously neat, everything in its place. A fluffy pink comforter covered the bed, a collection of stuffed animals lined the headboard.
Lizzie stepped inside, her gaze sweeping over the room, a strange expression on her face. “This is… Emma’s room. What are we doing in here?” Her voice was barely a whisper.
“This is where the party starts,” he murmured, his voice thick with anticipation. He walked over to Emma’s dresser, a white, slightly chipped piece of furniture. He pulled open the top drawer. Inside, neatly folded, were Emma’s clothes. Small, innocent things. Cotton bras, tiny panties, pastel-colored camisoles.
Lizzie’s eyes widened, her breath catching. “Kai… what are you thinking?” Her voice was hushed, tinged with a mixture of apprehension and a growing fascination.
He pulled out a pair of plain white cotton panties, small enough to fit in his palm. “I want you to put these on.” He held them out to her, his gaze unwavering.
She stared at the underwear, then at him, her lips slightly parted. A flush crept up her neck, staining her cheeks. “You want me to wear… Emma’s underwear?” Her voice was barely audible.
“Yes,” he confirmed, his voice firm, leaving no room for argument. “And her bra. And one of her dresses.” He gestured towards the closet, where Emma’s modest wardrobe hung. “I want you to be her. For tonight.”
Lizzie’s chest rose and fell rapidly, her eyes darting around the innocent room, then back to the small cotton panties in his hand. “Kai, this is… messed up,” she breathed, a nervous laugh escaping her. “This is really messed up.” But her hand reached out, slowly, hesitantly, and took the underwear from him. Her fingers brushed his, a jolt of electricity passing between them.
“Is it?” he challenged, stepping closer, his body heat radiating against hers. “Or is it just… exciting?” He watched her face, the way her pupils dilated, the way her tongue darted out to wet her lips. He knew he had her.
She held the underwear, turning it over in her fingers. “Exciting and messed up aren’t mutually exclusive, you know.” Her voice was still quiet, but the initial shock was giving way to something else, something darker, more adventurous. “What else do I have to do?”
“When you wear them,” he began, his voice dropping to a low growl, “I want you to call me ‘big brother.’” He watched her carefully, waiting for a definitive rejection, but it didn’t come. Instead, a shiver ran through her, visible even under her tank top.
She looked at him, her eyes now burning with a fierce intensity. “Big brother?” she repeated, the words tasting foreign on her tongue. “You’re serious.” It wasn’t a question.
“Dead serious,” he confirmed, his own excitement building to a fever pitch. “I want to fill you up, Lizzie. Repeatedly. In her clothes. In her bed. And I want you to call me big brother every time.”
Lizzie swallowed hard, her gaze fixed on his. “Okay,” she whispered, the single word a surrender, a promise, a challenge. “Okay, Kai. Let’s do it.” She turned her back to him, her fingers already fumbling with the hem of her tank top. “Turn around,” she instructed, her voice a little shaky, but firm.
He watched her reflection in the small mirror above Emma’s dresser as she stripped, her movements deliberate. Her black tank top came off first, revealing her full, dark nipples already hard. Then her own lace thong, a stark contrast to the innocent cotton she was about to put on. She stood naked for a moment, her body a canvas of curves and shadows, before reaching for the white cotton panties.
She pulled them on, the fabric stretching taut over her hips, riding high on her stomach. They were snug, much smaller than her own underwear, and she had to tug at them to get them to sit right. “They’re a little… tight,” she commented, her voice a low murmur, a slight strain in her tone as she adjusted them. “She’s so tiny.”
He watched her, a primal urge stirring deep within him. “Perfect,” he rasped, his voice rough with desire. “Now the bra.” He picked out a small, pale pink training bra from the drawer, the kind with no underwire, just soft cotton cups.
Lizzie took it, her fingers tracing the simple fabric. She fastened it behind her back, her breasts spilling slightly over the top edges of the cups, the soft cotton doing little to contain their fullness. Her nipples, dark and prominent, pressed against the thin fabric, visible beneath. “This is… ridiculous,” she said, but a smile played on her lips, a mixture of amusement and pure, unadulterated naughtiness.
“You look… innocent,” he said, his eyes devouring the sight. “And completely corrupted.” He walked to the closet and pulled out a simple yellow sundress, the one Emma wore to church sometimes. It was modest, knee-length, with thin straps.
She took it from him, her fingers brushing his. She slipped it over her head, the soft fabric falling around her body. It was a little short on her, riding higher up her thighs than it would on Emma, and the bodice was tight across her chest, pulling at the seams. “I feel like I’m playing dress-up,” she said, turning to face him, her eyes sparkling. “A very naughty game of dress-up.”
He reached out, his fingers tracing the outline of her collarbone, then down to the thin strap of the sundress. “Exactly. And now, for the rules of the game, little sister.” His voice was low, a husky whisper that sent shivers down her spine.
Her eyes met his, wide and expectant. “Rules?”
“Rule number one: You are Emma. You are my sweet, innocent little sister.” He watched her carefully, noting the subtle shift in her posture, the way her shoulders softened slightly. “Rule number two: You will call me big brother. Always.” He paused, letting the words sink in. “Rule number three: You will obey your big brother. Without question.”
A slow smile spread across her face, a dangerous glint in her eyes. “And what does big brother want his little sister to do?” Her voice had taken on a slightly higher pitch, a softer quality.
“Big brother wants his little sister to get into bed,” he commanded, gesturing towards Emma’s pink, fluffy bed. “And wait for him.”
She nodded, a demure dip of her head, completely unlike the Lizzie he knew. She walked to the bed, her steps a little hesitant, as if she were truly embodying a younger, more innocent girl. She climbed onto the bed, pulling the comforter up to her chin, her eyes fixed on him.
He watched her, his heart pounding in his chest. This was it. The moment of truth. He walked to the door, closing it softly, plunging the room into a dim, intimate twilight. He turned back to her, his gaze intense.
“Are you ready, little sister?” he asked, his voice a low rumble.
She nodded, her eyes wide, a flicker of apprehension mixed with excitement. “Yes, big brother.” Her voice was a soft whisper, almost a plea.
He moved towards the bed, his eyes never leaving hers. He sat on the edge, the mattress dipping under his weight. He reached out, his hand gently stroking her hair, pushing a stray strand away from her face. “You’re such a good girl, Emma.”
A soft moan escaped her lips, a sound of pure pleasure. “Thank you, big brother.”
He leaned in, his lips brushing her forehead. “Big brother wants to make sure his little sister is comfortable.” His hand moved from her hair, down her cheek, then to her neck, his thumb tracing the delicate pulse point.
Her breath hitched. “I’m… I’m comfortable, big brother.”
He moved lower, his fingers brushing the thin strap of the sundress, then the soft cotton of the bra. “Are you sure? This bra looks a little tight.” He gently pulled at the strap, his fingers brushing the swell of her breast.
“It’s… it’s fine, big brother,” she stammered, her eyes fluttering closed for a moment. A soft blush bloomed on her cheeks, staining them a delicate rose.
He leaned closer, his voice a low, seductive murmur. “But I want you to be perfectly comfortable, little sister. Big brother wants to make sure nothing is bothering you.” His fingers deftly unhooked the back of the small bra, and the straps slid down her shoulders, freeing her breasts. They spilled out from the yellow sundress, full and magnificent, her dark nipples already erect and pointing towards him. The pink cotton bra lay innocently on the comforter beside her, a stark contrast to the raw desire now radiating from Lizzie.
She gasped, a sharp intake of breath. Her eyes, now wide open, met his, a mixture of shock and arousal swirling within them. “Big brother,” she whispered, her voice barely a breath.
He leaned down, his lips brushing against one of her exposed nipples. He tasted the soft skin, felt the hard peak against his tongue. “So sweet,” he murmured, suckling gently. A low moan escaped her, her fingers gripping the comforter. He continued to tease her, his tongue circling the sensitive skin, occasionally taking the whole nipple into his mouth and pulling, eliciting a soft whimper from her.
“Oh, big brother,” she pleaded, her hips beginning to writhe subtly beneath the yellow dress. “Please…”
He pulled back, his eyes dark with hunger. “Please what, little sister?” He watched her, enjoying the delicious torment, the way her body arched towards him.
“Please… make me feel good,” she begged, her voice thick with desire.
He smiled, a predatory gleam in his eyes. “Big brother will make you feel very, very good. But first,” he reached down, his fingers finding the hem of the yellow sundress, “this dress looks a little constricting,