Koro Syndrome is mostly found in China, Japan, and India. It's the obsessive fear that the genitals are shrinking, or retracting into the body, and that when they finally do disappear, you will die. How does a doctor even begin to treat such a syndrome? Take a look at a very strange, and specific, delusion.
Koro goes by many names because it spans several cultures with different languages. It's thought that the term "koro" comes from Malay, and refers to a turtle's head as it retreats into the shell. Considering that koro syndrome is the belief that the genitals — usually the penis but in women's case, the nipples — are retreating into the body, the metaphor is apt, but disturbingly vivid. Since it's purely a psychological disorder, the main dangers of koro are health problems caused by anxiety, and the occasional practice of either asking other people to take hold of the genitals and pull them back out, or trying to pull them back out of the body oneself.