Citizen (noun):
A person owing loyalty to and entitled by birth or naturalization to the protection of a state or nation. A resident of a city or town, especially one entitled to vote and enjoy other privileges there. A civilian. A native, inhabitant, or denizen of a particular place: “We have learned to be citizens of the world, members of the human community” (Franklin D. Roosevelt).

Denizen (noun): An inhabitant; a resident: denizens of Monte Carlo. One that frequents a particular place: a bar and its denizens. Ecology: An animal or a plant naturalized in a region. A plant, animal, or person that legitimately belongs in a certain area or place, whether they reside there or appear there frequently, as violets are denizens of the wood, fish are denizens of the deep, and criminals are denizens of jails

Chiefly British: A foreigner who is granted rights of residence and sometimes of citizenship, without rights of holding office or inheritance. The British sense, however, implies a process (to be denizened in a country) and the status of "denizenship" (to have rights of denizenship revoked).
"I am a denizen of Camden County," suggests a much deeper and more intriguing involvement in the county than merely saying, "I am an inhabitant of Camden County" or even "I am a native of Camden County." (Keep in mind, though, the animals (dogs, cats, etc.) who live in Camden County are also denizens, not to mention the birds and the trees they nest in. )
"The denizens of QMUOL are generally accepted in the best colleges and universities."