Elena's friend Juan took her to a very secret place to attend a party. Elena was very happy, but she never expected that she would become the last victim of the famous perverted killer Night Demon. After kidnapping Elena, Night Demon threw her into an abandoned hotel. The hotel had been abandoned for many years. Under the modification of Night Demon, it has become a complex maze full of organs and dangers, and Elena was deeply trapped in it and could not move. After learning that his daughter was missing, Elena's wealthy father found a mercenary army to rescue his daughter. But the mercenaries knew nothing about the perverted killer Night Demon. In desperation, Elena's father had to find a young man named Alkin, who was the survivor who had successfully escaped from the hands of Night Demon. At the request of Elena's father, Alkin embarked on a terrifying journey to face Night Demon again...