Li Xu moved into the old apartment "Qiwu Building" inherited from his deceased aunt on a rainy night. He appeared to be gentle and considerate, but in fact he was a "yandere landlord" trapped by childhood trauma and a mysterious contract. He signed an inviolable residential contract with his tenants through a copper key engraved with runes, and violators would be punished. When his uncle Li Zhenguo's family, who had abused him, tried to rob the property, Li Xu set a trap and imprisoned them in the building, launching a liquidation and revenge in the name of "contract". However, with the awareness and resistance of the tenant Chen Bo, the power of the contract became abnormal, and the dark power backfired. Li Xu had to choose between hatred and protection. However, the escaped cousin Li Wan devoted herself to the more powerful darkness due to her obsession, and vowed to come back for revenge...
