The main character, Yuka Inose, has moved to a high-rise tower apartment with her family. As soon as she moved in, she was taken away from the apartment mount by the residents who said "upper floor is better". Yuka tries to get used to her life even though she feels uncomfortable. However, one day, she takes on a board member from her neighbor, and she becomes involved in the Darkness of this apartment...

Chitose was abandoned by her boyfriend and transferred to the culture club, which she did not want to be a part of. She is assigned to play shogi, a game in which she has no interest. She is eager to follow in the footsteps of the handsome shogi player Shijo Heki and make a name for herself, but she is at a loss in a world she doesn't know...