Going Postal: Mr Pump

Mr. Pump is a golem who is tasked with serving as a parole officer-slash-assistant to Moist von Lipwig.  Mr. Pump got his start in the golem business by working in a hole pumping water (hence the name) for 240 years - his creators had failed to tell him when he was supposed to stop pumping, and golems never stop performing a task until said task is completed.  His tracking skills are impeccable - Moist von Lipwig is powerless to escape him.