reprobate
/ˈreprəbeɪt; `rɛprəˌbet/ adj, n [attrib 作定语]
(fml or joc 文或谑) immoral or unprincipled (person) 道德败坏的（人）; 堕落的（人）
have reprobate tendencies 有堕落的倾向
You sinful old reprobate! 你这个作恶多端的无赖!
He has always been a bit of a reprobate. 他一向不很规矩.