Tired and disillusioned with her busy life in Tokyo, Kurumi Oki decides to slow down and move to Hokkaido for a fresh start. One night, on the train home from meeting up with her friends, she dozes off and realizes she has missed her stop. Panicked, she gets off the train and finds herself at an unfamiliar station called Kamuy Mosir. Seeking help she walks toward some nearby lights, where she sees a group of people dressed in unfamiliar costumes having a party. Without warning, she is chased by the group and is captured by a young man. Her captor tells her that she is…