An Illusion of Paradise

Enter Cosmia, a beautiful city of the 30th century, forged from the ruins of what was once New York. Under the facade of a paradise lurks something much darker.
As a result of overpopulation, once a year, during the Blood Moon, the highest officials in the city select 100 people between the age of 12 and 18 to be culled for the better of the city.
To the people, it's considered the greatest of honors to be chosen and sacrifice yourself for the better of the rest. The families of those culled are given large sums of money, food, and have high-up job opportunities offered to them. The people culled are never seen again, or so everyone thought.