奸 - wickedness, mischief, rudeness

wiles and cunning; craftiness and treachery

someone who curries favor with their master while secretly plotting against him

Chinese traitor (esp. a collaborator with the Japanese)

cunning and wickedness

wicked person; evil thing

evil thief; wicked robber

evil design; crafty plan; plot

disloyal retainer; treacherous subject

letter explaining the reasons for cutting down an alleged villain; assassin's written vindication of his killing

villain

cunning; craft; wiles

shrewd (dirty) trick; sinister scheme (design); sly art