Beautiful sisters who work as nurses. Yukine (sister) feels something is wrong with Yura (sister) who met after a long time, and is transferred to the hospital where her sister works to find out the cause. One day, at the hospital at midnight, I witnessed a younger sister who was made into a sex slave sucking on the patients' cheeks and being raped. With the cooperation of senior nurse Yoshioka, I approach the darkness of the hospital with the desire to help my sister ...