A large heavy-set corpse, Prestwick was clearly an overweight man in life. Areas of excess flesh hang from his skeleton, particularly around the jowls. He still retains the habit of attempting to rest his hands on his once-corpulent stomach, although it no longer exists. In its place is a nest of restless cockroaches which no amount of prodding or cleaning seems to remove.

Preswick is conscious of his appearance - his hair is always neatly combed, his clothes washed and pressed, his skin as clean as is possible for a festering corpse. He wears an almost permanent expression of disgust, as he finds his current physical state repulsive.

He wears thick glasses, which in contrast to the rest of his clothing are often smudged and grubby.