The term 'THEY CLEAN UP' refers to janitors, who are responsible for the cleaning and maintenance of buildings. Janitors typically perform a variety of tasks such as sweeping, mopping, vacuuming, dusting, and emptying trash cans. They may also be responsible for minor repairs and upkeep of the building, such as changing light bulbs and unclogging toilets. Janitors often work in shifts and may be required to work nights and weekends.