While preparing for a date with my girlfriend, I was waiting in the living room when her older sister suddenly came home from an overnight stay. She was dressed provocatively, wearing an outfit so revealing it was nearly lingerie, looking so sexy it was hard to know where to look. Suddenly, she started provoking me by giving me a handjob. Though I truly care for my girlfriend, I couldn't resist the temptation of this lustful older sister. The teasing escalated quickly—secret blowjobs, then her coming on to me at night, aggressively riding me. I got completely drawn into her seduction. Overcome with thrill and guilt, I was eventually caught by my girlfriend. But it didn't matter—completely out of control, I ended up pounding her sister hard and filling her with a creampie, leading to a shocking turn of events!