In our living space. In fact, there are multiple dimensions. Each dimensional space is completely independent and does not interfere with each other. Only occasionally due to certain factors colliding with each other, there will be intersection. This is why some people occasionally encounter ghosts and demons! Such non-homogeneous species. Normally, non-similar species cannot touch each other's entities unless there is a carrier.
In this book, we will rank the dimensions numerically for ease of memory. Our human dimension is the seventh dimension. Life in this dimension can be said to be the most routine and normal. Of course this is from our human perspective. Perhaps we are the most abnormal in the eyes of species from other dimensions. These are all digressions. The protagonist this time will lead readers to different dimensions to experience the "exotic scenery".