Im Jun-hoo was just your regular student, working a part-time job and trying to study for the college entrance exam to fare better this time around. But something had changed. Every night he found himself in a dungeon, forced to eat filth and compete to ascend in the ranks. He was also rewarded for his hardwork in the dungeon and his life slowly begins to change. He has a new goal now: pass the college entrance exam and ascend the ranks of the dungeon. Will he succeed?