Asami Sae is a housewife, married to a doctor, and has two daughters. Her family lives within the exclusive SKY CASTLE neighborhood. She works hard to get her eldest daughter into the most prestigious high school, and she will do anything to accomplish that goal. Her neighbors in SKY CASTLE include Minamisawa Izumi, Nikaido Kyoko, and Natsume Misaki. All of these women try to send their children to the same elite high school.
They hear that the son of their neighbor, Saejima Kaori, has passed the entrance exam to the high school that they desperately want their children to attend. They are eager to hear from Saejima Kaori on what was used to help her son pass the exam. Saejima Kaori reveals the existence of exam coordinator Kujo Ayaka. Kujo Ayaka only tutors two students a year and charges an extraordinary fee, but she gets her students into any school that they want. She boasts a 100% success rate.