I once knew a girl who saw "angels". She saw
them ooze out of the ceiling, hovering around
in the rafters. She was also a multiple-med
schitzo. Also not such a puritan for someone
who saw 'angels' everywhere ......
The pills helped ... but were not 100% effective.
People "see" what they want to see. It's oft
very 'real' for them, very compelling.
Alas that does NOT mean they're seeing anything
remotely real.