be a devil! イディオム
Speak of the devil!
If you are talking about someone and they happen to walk in, you can use this idiom as a way of letting them know you were talking about them.
be a devil
A byword advised to animate addition to do something, abnormally article they are afraid or borderline about. Primarily heard in UK. A: "Oh, be a devil and get dessert." B: "But what about my diet?"Learn more: devilbe a devil!
said back auspicious addition to do article that they are afraid to do. informal
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