Loop by Koji Suzuki

A scientist involved with a massive virtual-reality project that recreates life on Earth discovers that the terrifying, seemingly supernatural phenomena others have blamed on a curse are actually emergent effects inside the simulation; as boundaries between simulated minds and the outside world collapse, the protagonist uncovers the project's origin — an attempt to preserve humanity after a catastrophic outbreak — and must face the ethical and existential consequences when memory, disease, and mortality persist inside a created reality. The novel blends psychological horror and speculative science to probe identity, responsibility, and what it means to be alive.

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