Take the lover home to play, the younger sister was "stolen" by the older sister

I and Mika have been dating for a while, today I was invited to her house. On the way there, Mika, afraid I would be embarrassed, told me about her sister, Ai-san. Her sister has a habit of... being nude at home! Even though she called ahead for her sister to prepare, when I arrived at the house and met Ai-san, I could clearly see her nipples through her thin shirt! Not only that, while sitting and eating cake together, Ai-san kept using her foot to touch my genitals, causing me to drop my chopsticks on the floor.

When I bent down to pick them up, in front of me was Ai-san's vagina completely exposed because she wasn't wearing underwear!!! Ai-san kept using her large breasts to seduce me, and I couldn't resist anymore and crazily had sex with her! The feeling of secretly having sex while my girlfriend was nearby, and especially being able to have bareback sex!!! Different from Mika, Ai-san allowed me to have bareback sex and ejaculate inside her! The pleasure of having sex with Ai-san made it impossible for me to get aroused when having sex with my girlfriend. I immediately went outside to find Ai-san. And then Mika found out too, but I didn't care, I wanted to have sex with Ai-san, wanted to enjoy the feeling of her big breasts and the pleasure of bareback sex. And in the end, I broke up with Mika and started dating her sister...