Hydra- A mysterious android that was created and confined in a laboratory that conducts illegal biological experiments. He was rescued by the police and taken to the university hospital where Azusa works. He doesn't know the common sense because he never went out. He is as straightforward as a child, but something goes wrong with Azusa's lust. Azusa Nagumo- A doctor who works at a university hospital in a lonely death course with a lot of work. She tends to be troubled and she is ordered to take care of Idol. She has no male experience.