FSDSS-497 Three Days of Being Pushed to the Limit by Her Older Sister While She Was Away: Yuko Ono

I was living with my girlfriend and planned to think about marrying her after I got a job following graduation. One day, her older sister Yuko came to visit our shared apartment, and after my girlfriend fell asleep, I ended up in a close and intimate mood with her sister. Later, when my girlfriend went out to a club meeting, Yuko came over again, and over the three days until my girlfriend returned, I was kept busy and worn out by her constant attention.