走后门

走后门:

Literally means:

enter by the back door

Actually means:

后门 figurativley refers to illegal or immoral means.

This phrase means attaining one's personal such as establishing underhand connections, pulling strings, or bribery; secure advantages through pull or influence. Derogatory.

后门，比喻不合乎规定的手段或途径。

走后门，比喻通过不正当手段（拉关系、托人情、送钱送物等）来促使有关人员为自己办成某事。具有贬义色彩。