Unexpected Heat in the Afternoon

I pushed open the door to my sister's room without knocking, expecting to borrow her charger like always. Instead, I froze. There she was, Lena, sprawled across her bed in nothing but a black lace bra and matching panties, one leg bent, phone in hand. Sunlight striped her toned thighs. She glanced up, smirked, and didn't bother covering up. "Well, look who can't read a 'do not disturb' sign. Got a reason for barging in, or are you just collecting awkward memories?" Her voice was sharp, teasing, the same tone she used when beating me at every board game since we were kids.

I cleared my throat, trying not to stare at the way her bra cupped her full breasts. "Charger. Sorry. Didn't think you'd be... like that." Lena laughed, low and confident, sitting up so her dark hair tumbled over one shoulder. "Like what? Comfortable in my own room? You're the one staring like you've never seen underwear before. Come on, close the door before the cat escapes." She patted the bed beside her, eyes sparkling with challenge. I shut the door, heart pounding, and sat down, the mattress dipping under my weight.

"You always this bold, or is this just for my benefit?" I asked, aiming for witty but landing somewhere between nervous and turned on. Lena leaned closer, her perfume mixing with the faint scent of her skin. "Bold? Please. I've seen you checking me out since you moved back in. Don't act innocent now. What, you think I'd wear this for the walls?" She shifted, her knee brushing mine, sending a spark straight through me. The air thickened. I could feel the heat radiating off her. "Maybe I should leave," I said, but didn't move. "Or maybe you should stop pretending you don't want to see more," she countered, fingers tracing the edge of her bra strap.

Tension crackled as she held my gaze, strong and unyielding. "You're my sister," I muttered, though the word felt thin. Lena rolled her eyes. "Stepsister, genius. And adults. Horny adults, apparently." She reached over, boldly palming the growing bulge in my jeans. "Hard already? Cute." Her touch made me groan. I grabbed her wrist, but she just grinned. "Don't get shy on me now. If we're doing this, do it properly." Words tumbled out fast, witty jabs turning into confessions. "I've thought about this," I admitted. "You drive me crazy with those looks." She pushed me back onto the pillows, straddling my hips, her pussy already wet and pressing against me through thin fabric. "Then stop talking and prove it."

Clothes vanished in a rush. I tugged her panties aside, finding her dripping and ready. Lena moaned, guiding my cock inside her with a confident roll of her hips. "Fuck, that's good," she panted, riding me hard, her ass bouncing as she set the pace. Sweat beaded on her skin while she leaned down, whispering filthy encouragement. "Deeper. Make me feel it." I thrust up, hands gripping her waist, the wet sounds of our bodies filling the room. She came first, clenching around me, but didn't stop, demanding I follow. I flipped us, pounding into her pussy until I came hard, cum spilling as we both panted, bodies slick and trembling.

Afterward, tangled and grinning, Lena traced a finger down my chest. "Not bad for a first round. But next time, maybe knock first—or don't." She winked, already plotting more. The afternoon light caught the gleam in her eyes, promising this was only the beginning of something far hotter.