물에 빠진 놈 건져 놓으니까 망건 값 달라 한다
속담
literallySave a guy from drowing, and he will demand you to compensate him for his mang-geon, or horsehair-woven headband; Save a stranger from the sea, and he will turn into your enemy; Save a thief from the gallows, and he will cut your throat
To ungratefully blame a person who did a favor after receiving help from him/her.
뜻풀이In Korean
남에게 큰 도움을 받고서도 그 고마움을 모르고 도리어 도와 준 사람을 원망한다.