Shinigami: This is Soul Society, Not Chaldea

When a Master from Chaldea awakens in the Soul Society, they quickly realize the rules have changed. No Command Seals, no Heroic Spirits—just Zanpakutō, Hollows, and a world governed by the Shinigami. Thrust into the afterlife's hierarchy with knowledge from another reality, our protagonist must navigate the deadly politics of the Gotei 13 while concealing secrets that could shake both worlds. Can a tactician trained to save humanity survive in a realm where death itself is just the beginning?