掐指一算姑娘你命里缺我扳指一算小伙你没我别活
[qiā zhĭ yī suàn gū niáng nĭ mìng lĭ quē wŏ bān zhĭ yī suàn xiăo huŏ nĭ méi wŏ bié huó]
Roughly means 'A quick calculation shows that you (a girl) are destined to need me; a snap of the finger shows a boy can’t live without me'. It humorously claims irreplaceability or indispensability, adding a bit of boastfulness or playfulness.