Internship in Junior Year, Joined the Bureau of Abnormalities and Became a Man in Black

[Main line of growth, multiple themes, partial group portraits, not brainless and cool] The whole family was brutally murdered, and the police have been pursuing it for decades. The case is still unresolved. Where is the real murderer? After decades of nightmares, are the demons in the dreams real or fake? And when the true face of the world is revealed in front of him, how should Su Mu choose?