My older sister is such a brat who dotes on me and always takes care of me so sweetly, which I'm really grateful for—but the way her plump, juicy ass looks from behind drives me wild, and I can never hold back. Even through her pantyhose, sometimes I notice she's not wearing any panties at all, and that sight turns me on like crazy. She once told me she got turned on watching a guy at work jerking off, got her panties wet and ended up taking them off—but I'm in the same boat, getting rock hard just from staring at my sister's sexy ass. When she notices, she'll rub her pantyhose-covered ass against my crotch and help me jerk off with her ass, grinding on me. Then her pussy gets soaked and she starts begging, "Fuck me from behind," and it always ends up the same way. Whenever she catches me masturbating alone, she immediately offers her ass, so her defenseless back view is my ultimate turn-on. Her anus opens up wide and twitches, and her soft, thick ass cheeks feel incredible when I squeeze them. I imagine slamming hard into her, watching her ass jiggling wildly with each thrust, and I cum almost instantly—but I wish I could keep watching longer, since the pleasure is just too intense and I climax too quickly. Sorry, sis... I came on your ass and ended up shooting inside you.