Rio and I had been dating for three months, and it was the first time I went to her house and the first time I got to know her sister, Anna. She has a beautiful face and a charming physique. When we were studying, she suddenly raised her legs to reveal the space between her thighs. Something? No underwear?! That's right! I can see your beautiful stream clearly! She deliberately opened it wider and did all kinds of poses to provoke me. And when my girlfriend was absent, she came forward and tactfully seduced me. I lost my mind completely and my cock couldn't stop thrusting deep into this seductive slit. I love my girlfriend, but her sister gives me a joy that I have never known before. And from then on, we both secretly made love to each other whenever my girlfriend was away...