““Unknown official” – literally “a person without a name”, where name means having some sort of fame rather than an actual name (kinda like “making a name for oneself”). Looks like no one heard of this guy until he suddenly got a huge promotion.

“Nuo opera” – look it up if you have the time, but in short, it’s a type of folk dramatic art. One of its most defining charactersitics is the usage of masks – like the kind you see in the manhua. Funnily enough, it originally had a religious rather than recreational meaning, and one of the common purposes of such rituals was to drive away demons (the irony of that will become apparent in later chapters).