Until her beloved sister marries the S family and becomes a masochistic man...

My sister married into a very wealthy and venerable family. I had so much trouble with the older sister who raised me as a parent. So I wanted to be happy when I got married. But... We were so close that we kept in touch with each other many times, but there was nothing to hear after the ceremony. I was curious, so I went to see my sister. There's no one in the mansion. I secretly entered the room where the door was open and found a DVD. It said "Record of impregnation of female slaves." I had a bad feeling...