Forgot the Key to Conquer the Demon and Seal the City

Under the modern city, demons and ghosts lurk in the darkness invisible to mortals. A small number of people with supernatural powers are called demon masters, and they are divided into three schools: swordsmanship, stick skills, and curses. Most of them belong to the secret organization Demon Slayer Sect. Meng Bufan was raised by his grandfather Meng Huaijin since he was a child, and learned the Meng family's demon-subduing swordsmanship. My grandfather left a prophecy before his death: On the 15th day of the eighth month of the Bingwu year, there will be a knock on the door at the old house in the east of the city. The Mid-Autumn Festival is approaching, and the wild ghost sealed by the ancestors of the Meng family three hundred years ago appears in the world and hurts people. During the battle, Meng Bufan got acquainted with Wen Renbai, a martial arts practitioner, and also uncovered his grandfather's unjust case: Meng Huaijin, the former branch leader of the Demon Slayer Sect, was expelled on unfounded charges because the seal he guarded was coveted. The seal is at its weakest on August 15th, and the three forces face each other in the east of the city. The barbarian ghost witch set up a trap and forced Meng Bufan to use his unique skills to suppress the world and suppress the barbarian ghost king again, but the price was that he forgot his original intention of defending the city. Zhen Qian Kun has the same source as the sealing power, this blow is equivalent to leaving the key in the lock. Both the inner ghost and the wild ghost are eyeing this key. Once they attack again, the seal will be completely broken. A battle around memory and fate begins.