Somebody who is Green / environmentally friendly on the outside, but Red / destructive on the inside. (Typically motivated by politics or environmental programs).
Can also be used to describe somebody who is kind / giving on the outside, but has cruel intentions hiding inside.
verb: When you hold a girls legs apart and begin to vigorously eat her out until said female orgasms all over your face leaving it covered in in the sweetvagina sauce, it is called this do to the resemblence to eating one of Gods greatest inventions, the watermelon.