Due to various circumstances, I ended up staying with my younger sister, a university student. One day, she caught a cold and had to stay home from school, and her kind and cute female friend came to visit her every day. I was jealous of my sister, so I decided to pretend to catch a cold, and my sister's friend nursed me back to health. What's more, I got a full view of her unprotected panties and breasts, which made me get an erection...