A liminal space is a place meant to be passed through rather than dwelt in — a corridor, a stair landing, a waiting room at night, a deserted pool — captured while standing empty. The aesthetic spread online from around 2019 and was shared explosively during the pandemic, when ordinary movement through such spaces had stopped.
There is no monster. The horror material is the mood itself: the strange blend of nostalgia and dread that wells up when a familiar place sits frozen with only the people missing. It is the visual foundation of the Backrooms and much modern internet horror — the prototype of fear that comes not from something happening but from nothing being there.