butter would not melt in one's mouth
01
used for saying that a person only appears to be nice or innocent, but they are not like that in reality
Dialect
British
British
Idiom
Informal
例
She acted as if butter would not melt in her mouth, but behind closed doors, she was always causing trouble.
Despite his sweet smile, he was a troublemaker at heart, with a mischievous nature that belied the appearance that butter would not melt in his mouth.
