男生劈腿时不怕扯着蛋
[nán shēng pī tuĭ shí bù pà chĕ zhe dàn]
This phrase humorously refers to the situation when a man cheats ('劈腿' literally meaning 'splits his legs') on someone else, adding that he doesn't care if he gets hurt ('扯着蛋' literally means pulling himself). This shows a kind of harsh criticism toward infidelity.