On a day of sudden downpour, my girlfriend's older sister, Mitsuki, came to my house soaking wet. "You live together, but you don't have sex every day? I'd do it if it were me." While she was away, I couldn't resist the temptation of her beautiful H-cup breasts and sweet voice... I lost all reason. I ended up having immoral sex with her again and again...! Her disheveled hair and wet divine breasts continued to arouse me, and I had sex with her beautiful waist in a cowgirl position on the sofa! I gave her a soft titjob in the bath! And she jiggled her divine breasts in bed! ...Even when morning came... we had fucked so hard that we'd released a lifetime's worth of sperm!