Homebody seems to be a tall humanoid, possibly up to 2.5 meters tall, with one arm somehow appearing under the stairs, and a long neck. Therefore, it
is implied that he can stretch out his limbs throughout the house through ventilation shafts, pipes or other entrances. It is also possible that his legs don't possess that quality.
It appears to be a whitish-skin it appears to have a skeletal body, therefore he look like its head is towards, its possibly up to 2.5 meter in height, another thing it has a hand nears a chair therefore that its going through a vent possibly.