Many have heard about this but for those who might not know, the creature called Phi Kong Koi is actually a Lao and also a Thai jungle ghost. It is kind of hard to explain or even characterized the appearance of it but a lot of people know it as a phantom with one leg. Legend says it moves by hopping with one leg while shouting, “Koi, koi, koi”.
It is said that the Phi Kong Koi jungle ghost will suck blood from the toes of any sleeping travelers when they are in the jungle. To avoid that from happening to them, travelers need to keep their feet together or even cross their feet when they sleep so that they are able to protect themselves from the Phi Kong Koi jungle ghost. It is indeed so scary.
There are people who said that the Phi Kong Koi are actually the real version of the Kha Ra Dae which is an ethnic group. This ethnic group is known to also hunt and possibly kill all the intruding humans in their territory. Other dark information about the Kha Ra Dae ethnic group would be that they usually take the meat of the victims to eat.
Sources: Wikiwand.