Fourth season of Strike the Blood.

Yan Yuechu returned to his hometown to work and made new friends at his workplace. One day, he went to XY Escape Room and found himself deeply attracted to the proprietor, Xu Aiyou. However, that was when he started to experience strange escape room illusions. As Yan Yuechu got to know Xu Aiyou, more and more incidents started to happen around him and even his friends. In the process of solving the escape rooms and finding the mastermind behind all these events, he gradually found himself uncovering the truth behind his lost memories...

An extraordinary guard walks in the desert of the western regions escaping the slaughter by the government. He took a surveillance assignment bound for the Chang capital. The task was thought of as something simple, but in reality it is a path full of crises and dangers. Here begins a journey that will affect the fate of the world.

Someday a group of classmates will perform a charm at night after school—the Happy Sachiko charm. This paper doll ritual is meant to make them stay friends forever, but performing it incorrectly will lead them to be dragged down into a dilapidated phantom of Tenjin Elementary School, which had been torn down years ago. Trapped until they can reunite and perform the charm correctly, the students will have to solve the mystery of the haunted school in order to make it out alive. Before that ill-fated event, however, the friends led ordinary lives. Corpse Party: Missing Footage reveals an insight into the students' lives on the day before they were thrust into a waking nightmare. [Written by MAL Rewrite]