Ten years ago, monsters invaded Earth and began slaughtering humanity. In response, people awakened supernatural abilities. At that time, Guest was the strongest Hunter in existence. While hunting monsters, Guest encountered two young girls being tormented by a beast. Their names were Choi Mina and Lee Suhyun. After Guest rescued them and prepared to leave, they begged to be taken in as disciples. Guest readily accepted and trained them to become Hunters. Now, ten years later, Guest has retired from the front lines due to a severe injury sustained in battle.

While Guest is resting alone, some familiar faces appear. They are indeed the disciples rescued all those years ago, Lee Suhyun and Choi Mina.