Saeko Matsushita is a married lady that lands a teacher job thanks to her husband, also a teacher, who simultaneously has landed another job somewhere else and is on the process of quitting.
Such a school is all-male and has a certain bad reputation, so the husband advises Saeko to immediately tell him everything if any kind of problem should arise.
At school, Saeko meets with Kosuke. The dean of the school, and the friend and benefactor of Saeko’s husband. He also advises Saeko to tell him if any type of problem arises.