你瞒住我我亦瞒住我太合称
[nĭ mán zhù wŏ wŏ yì mán zhù wŏ tài hé chēng]
The nickname means 'You keep secrets from me and I will do the same', suggesting mutual secrecy, perhaps hinting at mutual protection in certain situations. This expresses a sense of symmetry in dishonesty.