Gang-u Choi is an ordinary high school student who likes video games. One day, he hears that his favorite game store is going out of business. When he visits the shop one last time, the store owner hands him a QR code for a mobile game. Gang-u starts up the game out of curiosity, but something feels off…. His mission is to drink 3 glasses of water?! When he decides to ignore the mission, he suddenly receives a penalty in real life! As the missions get more dangerous, will Gang-u be able to protect his reality?