Within the shadows that plague the outside world, Yu Hong discovers refuge behind the walls of a safe house—a sanctuary from the relentless terror beyond. But safety proves fleeting when a mysterious black mark appears on his body, granting him an extraordinary ability: the power to fortify all things around him. As unkillable phantoms and endless monsters press against his refuge, Yu Hong harnesses this enigmatic force to transform his shelter into an impenetrable fortress. With each reinforcement, his haven grows stronger, more resilient, more absolute. What begins as a desperate escape becomes a methodical construction of an unshakeable domain—a world within a world where nothing can breach his defenses and nothing threatens his survival.