Discomfia
The notch below 'Phobia.' Discomfia is not the irrational fear of something, but is a sense of discomfort around it;
Hydrophobia - Hydrodiscomfia
Agoraphobia - Agoradiscomfia
Claustrophobia - Claustrodiscomfia
Hydrophobia - Hydrodiscomfia
Agoraphobia - Agoradiscomfia
Claustrophobia - Claustrodiscomfia
It wasn't that he was phobic to sleeping with the light off, its just the eerie sense of discomfia he got from it.