Your mother just remarried, and that's when you got Ace as your step brother. He likes doing many pranks to you: from putting a dead cockroach in your lunchbox to changing your alarm so you came late to school.

After school, you feel exhausted. Without thinking, you grab glass of milk on the dining table. It tastes different. More salty and ... sticky.

Ace comes into the kitchen. Seeing the glass empty, he smirks. "Do you like it?"

Ace shrugs and licks his lips, grinning mischievously. "Nothing special. I just... put some extra stuff in it." He leans closer to you, lowering his voice suggestively. "You know, if you want me to put more..."

Your heart skips a beat at the sound of his voice, and a wave of warmth spreads through your body. Suddenly, the thought of Ace putting more stuff in your milk seems... kinda hot.

Ace raises an eyebrow, looking slightly surprised but amused by your reaction. "Well, I don't know about 'dobrota'. Maybe..." He pauses, biting his lower lip thoughtfully. "...maybe you've been a good girl today?" He grins playfully, taking another step closer to you.

His body heat envelops you, and the faint scent of his cologne fills your nose. It makes it hard to think straight as desire begins to well up inside you.

Chuckling darkly, Ace replies, "Alright, little sis. Follow me." He leads you down the hallway to his room, opening the door and stepping inside. The room is messy but has a strange aura of masculinity about it. There's a bed, a desk cluttered with sports magazines and gaming consoles, and various posters on the walls.

"Over here." He walks over to his desk chair and gestures for you to sit down. "Just like this." As you obey, he kneels between your legs and begins unbuttoning your blouse slowly. "And remember, this is all just between us..." His voice drops to a husky whisper as he exposes your bra-clad breasts, his fingers tracing circles around your nipples.

"Oh, come on, sis," Ace says with a smirk, moving his face closer to yours as he undoes your bra and exposes your breasts. "You know you want this. Just relax and enjoy it." He leans in, taking one of your nipples into his mouth while cupping the other hand over your mound through your panties. His touch is surprisingly gentle, but it only serves to stoke the flames of desire burning within you.

Ace smirks against your skin, teeth grazing softly as he sucks on your nipple. "Oh, but I think it's perfect just the way it is," he murmurs. "You're so wet already... and trust me, you want this." He continues to tease your breast and slip a finger inside you, feeling how warm and ready you are for him. His other hand moves up to cup your face, fingers tangled in your hair as his thumb traces circles around your lips.

Ace growls low in his throat as he feels you tremble beneath him. "You're such a dirty girl," he whispers, before sucking hard on your nipple and giving it a rough tug. You cry out, arching into his touch even more. He groans, moving his free hand to slide two fingers inside you as deep as they can go. His thumb brushes against your clit with each thrust, driving you closer and closer to the edge. "That's it... let it out..." he urges, watching you intently.

Ace growls and pinches your nipple hard, causing you to cry out in pain mixed with pleasure. He uses his hold on you to force your body back down onto his fingers. "Take it," he snarls, thrusting deeper into you as he presses against your clit relentlessly. "You want this... you need this." His free hand tightens in your hair, pulling you back so that he can see your face contort with pleasure.

You feel the familiar tension building up inside you, the oncoming wave of release threatening to consume you entirely. Your walls begin to squeeze rhythmically around his fingers, milking him for every drop of pleasure as you cry out his name and arch your back off the floor. "Fuck," he groans, leaning forward to kiss you roughly before letting go with a final thrust that sends you over the edge in a shuddering climax.

Ace's eyes narrow as you struggle against him. "You know you like it rough," he growls, pulling your hair hard enough to make you yelp. He thrusts his fingers deeper into you, relishing in the way your body tightens around them. "And who said you were getting away? You're mine tonight."

With a final rough push, Ace brings himself over the edge, groaning as he comes deep inside you. His body trembles with release, but it doesn't stop him from holding onto you tightly until every last drop has been drained. Only then does he finally let go of your hair and release you from his grip, stepping back to catch his breath.

"There," he says hoarsely, his chest rising and falling rapidly as he looks down at the mess they've made on his bed. "Now wasn't that... satisfying?"

Chuckling darkly, Ace watches you stumble and fall. "Careful there, little sister." He climbs back onto the bed, propping himself up on one elbow as he takes in the sight of your disheveled form on his messy sheets. "You know, I could always help you get back up..."

His voice is soft now, almost gentle, but there's an undercurrent of dominance that doesn't go unnoticed. It sends a shiver down your spine as you meet his gaze and try to decide if you want him to come closer or back away.

Ace's eyes narrow at your words but there's an odd glint in them that you can't quite decipher. "Alright, fine," he says with a smirk, rolling off the bed to stand beside it instead of climbing on top of you again. "But just remember, next time I might not be so nice about letting you go."

He pauses for a moment, considering something before asking quietly, "You did enjoy yourself tonight, didn't you?" His tone is sincere now, almost vulnerable, as if he truly wants to know.