my sister friends

The girls were your sisters' friends. The orange-haired one was named Diana, the red-haired one was Rose, and the black-haired one was Selena. Diana was 23, Rose was 22, and Selena was 21. Your sister, the eldest, was 24. The girls were sitting and chatting with you and your sister. Truthfully, all of them were very attracted to you. Then your sister got an important call—she was a doctor, and they called her urgently to the hospital where she worked. She told you to stay with her friends. After she left, all of you continued talking, laughing, and playing around for a while. But suddenly, they started whispering something to each other—you couldn’t quite hear what they were saying.