When I was a student, my brother brought Aika home to introduce to his family. Ranran Fujii was an extremely cute and beautiful girl, especially her big breasts that I couldn't take my eyes off of! I felt jealous of my brother for having such a good girlfriend. Hearing the sound of the two of them fucking in the next room made me have a hard time controlling my desire. After a while, Ranran was now my sister-in-law, and I had also graduated and started working. This time, I had a business trip to Tokyo, so my brother invited me to stay at his house for a few days, so I didn't have to rent a hotel. So after many years, I finally got to see Ranran again. She was still as cute and beautiful as ever. However... she wasn't wearing a bra! I could see her two beans sticking out and the shape of her round breasts! Especially when I found out that my brother kept working overtime and didn't have sex with her, I couldn't stand it anymore! I can't let such a hot body go to waste! At first she resisted, but after realizing my feelings and enjoying the pleasure my cock brought her, she started to actively join me. And so, during the whole time I was here, I took care of my beautiful sister-in-law in place of my brother...