SSIS-845 Sorry but I want to fuck your sister more

My girlfriend and I have been living together in Tokyo for four years. She never thought about getting married. She always had to work the night shift and then go back to sleep in the morning, so I haven't had sex with her in three months. The university entrance exam is about to take place, Adachi Yuri, my girlfriend's younger sister, is going to Tokyo to take the exam, so she stays at my house for a day. She is really beautiful, and she doesn't wear a bra, so when Looking at my penis, it automatically stood up. While we were in the bathroom, suddenly there was an earthquake. My brother and I were so close together that he discovered my penis was standing up. pointed straight at her. And from that moment, she began to tempt me, making me ejaculate continuously inside her. I know you like me, every time I talk about buying a house with my girlfriend, you sulk....