To prepare for my national university entrance exams, I ended up staying at my relative's house, a beautiful older sister who graduated from a prestigious university, for intensive private tutoring. After seven years, she still had traces of her youthful charm, but her mature allure was overwhelming. While studying, I couldn't resist her unconsciously alluring denim-clad, voluptuous ass, and my rationality flew out the window. I couldn't hold back my pent-up desire, so I impulsively went for it right there! Feeling so good, I accidentally ejaculated inside her. I thought I'd get scolded, but she gently squeezed my exposed cock between her vaginal folds, saying, "Be good and study later?" She repeatedly squirted my semen, creating a summer memory I'll never forget.