(exp)those who resort to blandishments and fawning smiles are apt to lack compassion; a honeyed tongue with a heart of gall→Related words:
巧言令色
あいつは口ばかりで、誠意がないね。巧言令色少なし仁とはよくいったもんだ。 They say fine words are no virtue if they're insincere and that's him in a nutshell. He's all talk but doesn't mean a word of it.
Japanese Dictionary
