Gang rape of my best friend's sister

Hikari Ninomiya was raped by a group of high school kids: Hikari Ninomiya was dragged to his house by his younger brother's friends, and had to serve him in all kinds of ways. Seeing that this older sister was so pretty and delicious, these kids planned to rape her. With Hikari Ninomiya's naivety, she was quickly taken away without any time to resist. Every day she is brutally fucked, what is the ending for her?