肮脏不堪的承诺洁白无瑕的爱情
[āng zàng bù kān de chéng nuò jié bái wú xiá de ài qíng]
It can be translated as 'A tainted promise, A pure love' - suggesting a conflict between something impure (such as a promise not kept) and true feelings; or describing a story involving a broken-hearted situation turning into an ideal romance eventually. It reflects an irony in reality sometimes.