love rat 薄幸郎;负心汉;爱情骗子

【例句】
I heard Mike had an affair. What a love rathe is!
我听说迈克有外遇了。他真是个渣男！

Love rats are terrible. They're people who cheat on their partners, and they're quite often men.
爱情老鼠的真正意思就是爱情骗子，指那些经常在恋人背后出轨的人。