I Entered an Academy in a Ruined Game

A veteran player of a ruined game has entered the game world! “Either die early, or live long enough to become a Ma-in.” In a world where ‘Ma-seong,’ which mutates monsters into demonic beasts, has become a zoonotic disease. Su-hyeon enters an academy that trains a special force called ‘Extermination Squad,’ created to fight hunters who were once heroes but have now fallen to become Ma-in. Can he counter the conspiracies of the Ma-in, defeat the true mastermind, and successfully achieve the clear he’s been wishing for? — Description from novelcodex.org