University student Hagoromo likes to tend to her studies, but it is not easy. She lives at a love hotel operated by her father. She lives with her older brother who is a detective and always asks her for help. It is not just that he is not good at his job. It is also that Hagoromo can travel in time. She has the ability to travel back in time and find out what happened when a crime occurs. As such, she is an arm of the detective agency.