F*cking My Best Friend's Little Sister

I shouldn't want you. Not when I've spent years guarding you like some loyal soldier-watching your back, keeping creeps away, doing the job your brother asked of me. You were just the kid sister. Braces and scraped knees, tagging along like our shadow, always underfoot, always looking up at me with those big, innocent eyes. But innocence doesn't last. Not when the girl I used to protect walks past me now with hips that swing like sin, breasts straining against too-tight tops, lips full and glossy-made for things I shouldn't be thinking about.
And you know it. You see the way my eyes follow you, how I stiffen when you lean in too close, how I grit my teeth when you smirk like you've already won. I tried to be good. I fought it. God knows I tried. But then you turned eighteen. Now you're legal. Lush. Untouchable only because I still pretend to have a shred of decency left. But summer's here. Your brother's away. And you're everywhere-half-naked in the pool, stretched out in tiny shorts, licking popsicles like you're starring in a f*cking porno made just for me.
The rules are gone. No one's watching. And I'm done pretending. You want me? You've got me. Bent over the kitchen counter, moaning my name with your panties around your ankles. Pressed against the wall, dripping for me, begging me to stop teasing and f*ck you already. No more hiding. No more games. This summer, you're mine. And I'm going to ruin you-in all the best ways.