Mio is 20 years old. Having lost her parents early, she and her grandmother run a traditional inn in Nagano. However, her grandmother gets sick. Mio moves to Tokyo and lives with her father’s best friend, Kyosuke. He runs a public bath. She begins to work at the public bath, but it is scheduled to be demolished to make way for redevelopment.
High School student Miyui Mashio is really struggling. She can't fulfill her dream of becoming an idol and her parents are always fighting. Suddenly, she finds a genie in a bottle and through an accident, finds herself back in 1991. She realizes she is now going to school with her parents. But the problem is, her parents do not seem to get along - so Miyui will never be born! Miyui learns her father is interested in idols and so together with her mother and other girls she forms the idol group AGS16 to make sure her parents will eventually fall in love.
The story is set in a big hospital which is infiltrated and taken over by an armed group wearing devil masks. Musashi Saburo a police officer on leave of absence has to save the hostages within a set time limit.
