蟊贼

蟊贼	máo zéi	insect that damages cereal crop seedlings / (lit. and fig.) vermin / a person harmful to the country and the people
蟊	máo	Spanish fly / grain-eating grub
贼	zéi	thief; robber / (bound form) traitor; subversive / (bound form) evil; wicked / sly; shifty; devious / (literary) to harm; to injure / (coll.) extremely; insanely; damn (common in NE China and Taiwan)