小三终究会败给小四
[xiăo sān zhōng jiū huì bài jĭ xiăo sì]
Translates to 'The mistress will eventually lose to the new other woman,' which refers to a common societal conflict within relationship dynamics where an affair gets usurped by another. In China, 'Xiao San' usually means 'the third party' or a person involved romantically with someone already in a committed relationship.