人不要脸天下无敌树不要皮必死无疑
[rén bù yào liăn tiān xià wú dí shù bù yào pí bì sĭ wú yí]
A rather provocative idiom that means 'A shameless person is invincible, but if you lose integrity, you are dead for sure.' It conveys disapproval for losing one’s self-respect.