Witchcraft, Kramer, and Malleus Maleficarum

Koro is a culture-bound delusional disorder in which individuals have an overpowering belief that their sex organs are retracting and will disappear, despite the lack of any true longstanding changes to the genitals.[1][2] Koro is also known as shrinking penis, and was listed in the Diagnostic and Statistical Manual of Mental Disorders.