My girlfriend and her sister have a Youtube channel called "Sister Bikinis". The views are quite high and both of them are quite famous. Today, my girlfriend asked me to help with filming a video and it was also the first time I met Sumire. From the first time, I was attracted by her hot body and revealing swimsuit. After finishing filming, my girlfriend and I went to her room, and we had sex right there. Sumire also secretly watched us, and when I went downstairs, she used her seductive big breasts to milk my sperm. In the evening, she sneaked in again and demanded to have sex with me even though my girlfriend was sleeping right next to us! She even allowed me to ejaculate inside her vagina, something my girlfriend had never allowed! And from then on, we continued to secretly have sex whenever we had the chance. That was until I was preparing to study in France with my girlfriend. But things didn't end so easily, Sumire invited me to have sex with her one last time, and that last time was discovered by my girlfriend...