腹黑

fùhēi
  1. (slang) outwardly kind but inwardly evil
  2. two-faced

CEDICT

slang

Entry Composition

1 腹 fù
  1. abdomen
  2. stomach
  3. belly
2 黑 hēi
  1. black
  2. dark
  3. sinister
  4. secret
  5. shady
  6. illegal
  7. to hide (sth) away
  8. to vilify
  9. (loanword) to hack (computing)