The Bahkauv was a beast that lived in the city of Aachen. When drunken men wanted to go back to their homes at night, it jumped on their backs so that they had to carry it’s weight and took a lot of time to arrive at their houses. If the men begged or prayed for the Bahkauv to go away, it became heavier. If they cursed and insulted it, the burden would become lighter.
Pic related, a statue of the Bahkauv in Aachen.