A teen disaster comedy about 3 girls who failed the grade. After spending nearly a year as a shut-in, Koto enters first year of high school for the second time. Together with fellow repeating students Shiki (held back due to poor health) and Tomoe (held back due to excessive free-spiritedness), as well as the expectation-immune, habitually late grade retention reserve army cadet Kaede, her experience of school life is rather different from the norm, but delightful in its own way.