The Monster Girl Locked Up in the Research Institute

This is my first novel. It's a sci-fi post-apocalyptic story. The male lead is one of the researchers developing a project, and takes part in an experiment. Before long, however, a biohazard breaks out somewhere. Dense fog engulfs the world, living things mutate, and the weather changes. Humans alone neither mutate nor develop superpowers, leaving humanity facing a massive crisis. The male lead has no choice but to step up and conduct various studies at the research institute, working "for the survival of humanity." Meanwhile, the world outside changes without him realizing it. By the time he emerges, he has no idea how much time has passed. But his return is when he begins to realize that the apocalypse has changed...