爷不狠女人难保妞不拽男人光跑
[yé bù hĕn nǚ rén nán băo niū bù zhuài nán rén guāng păo]
A somewhat chauvinistic sentiment is expressed here, saying 'if men don't act fiercely (be serious), they cannot attract girls and then only see the boys running.' It portrays traditional gender role expectations, but it can also be taken as exaggeration in humor.