Reenacting the Unsolved Case: And Thus, Death Smirks

There exists an unusual shinigami.

This shinigami desires to solve mysteries, and searches for souls who dedicated their lives to solving unsolved cases but were unable to succeed, calling them to its dwelling place.

This place is a library housing countless memories of the dead preserved as books, and also serves as a quasi-detective agency where the shinigami solves mysteries.

Using the memories of the dead and divine powers, the shinigami creates a simulated stage of the unsolved case in the form of a book. It then has the soul participate in this recreation, enjoying the mystery-solving process from that soul's perspective.

Should they fail to solve the mystery, the soul will cease to exist. Even if they succeed, the dead cannot be brought back to life, nor can the past be changed. Only the truth becomes clear.

Nevertheless, the souls desire to uncover the truth behind these cases and accept the shinigami's terms.

This time, the one who visited this shinigami detective agency was...