As for what the inner world is, it is a misalignment of dimensional dimensions. In the game he recognized, the space-time where we humans normally live is considered the outer world, while the scenery of the middle world is not a place where humans can survive, filled with blood and monsters everywhere. As for the inner world, it can be described entirely as hell.
Of course, Kevin also pointed out that the flow of time here is different from reality, a day in reality is only a few hours here. When the church bells ring, the sky would quickly darken, and the dimensions of the dimensions would also switch rapidly at the moment the bells sound.