Post Otto Stress Disorder

Post Otto Stress Disorder, also known as POSD is a mental disorder usually known to happen in people who have played Honkai Impact 3rd, a game where there is an antagonist known as Otto Apocalypse. People with POSD are all afraid of any blonde man, in fear that they are actually just Otto Apocalypse.

"Hey, did you know person has POSD?"
"No? What even is that?"
"It's Post Otto Stress Disorder."
"Explain."
"Person thinks that any person with blonde hair is actually Otto Apocalypse"