scummy
scum-my
adjective
Despicable, morally reprehensible, or untrustworthy.
"He's a scummy bloke who'd steal from his own mother."
adjective
Covered with or resembling scum; dirty or unpleasant.
"The pond was scummy and stagnant."
Thesaurus
Synonyms: unclean, dirty, soiled, miserable, low-down, low, scurvy, abject, contemptible