Today is Friday, and the department head Momoko, who has an important meeting coming up on Monday, was working with her subordinate Ota to prepare the materials. However, they couldn't find the documents anywhere in the archive. Suddenly, the lights in the archive went out. Now that I think about it, I seem to have seen a notice saying 'Power outage due to facility inspection'―. The door, electrically locked, doesn't budge. Other employees have gone home and there's no charge left on their phones. In that critical situation, in the narrow and suffocating archive, Momoko finds herself spending until Monday with her young subordinate...