I found the guy you're talking about - in the upstairs room, sort of awkwardly positioned with his head right on the corner of the pillow.
Interestingly the designers (or whatever job title sets up decorative NPCs like that) seem to have done that quite deliberately, because the equivalent /doze position for players is positioned right in the centre of the pillow and facing the other direction. A specially-shaped pillow would be necessary for them to lie like that comfortably.
Some screenshots I had taken of my character's doze positions a previous time this conversation came up:
POSE 1:
Horn goes straight into the pillow.
POSE 2:
Not really a sleep pose.
POSE 3:
Sleeping on back, tilted to not squash tail.
Actually quite viable with this horn type, depending on the position of secondary horns from the hairstyle. I'm not sure how far back the other horn designs go by comparison.