unspoken rules (usually ones that codify improper behaviors such as leveraging guanxi to get favorable treatment, or coercing employees for sexual favors)
趁势
chèn shì
to take advantage of a favorable situation / to seize an opportunity
(lit.) to wither in the light of day / (fig.) the bubble bursts as the reality becomes apparent (esp. of a much-anticipated first meeting with sb) / (of stocks) just as the favorable news is officially published, the stock price falls
天公作美
tiān gōng zuò měi
Heaven is cooperating (idiom) / the weather is favorable for the planned activity (a variation of 天公不作美|天公不作美[tian1 gong1 bu4 zuo4 mei3])
陪睡
péi shuì
to trade sex for favorable treatment (career advancement, higher grades, rent-free accommodation etc) / to sleep in the same bed as one's child
业配
yè pèi
(Tw) (media) writing an article or creating a video favorable to a business in return for payment from the business (abbr. for 業務配合|业务配合[ye4 wu4 pei4 he2])
开花结果
kāi huā - jiē guǒ
lit. to blossom and bear fruit (idiom) / fig. to come to fruition / to yield favorable results
lì