Koteka is one of West Papua unique traditional protector of male genital. Modern society may see it as uncivilised traditional clothing that should be vanished from the world. However, it is one of our identity, at least in the perspective of the development of tribesmen in the land of Papua. We might transform our clothing into modern style, but we would never forget our identity.
Here is a short explanation:
The koteka, horim, or penis sheath is a phallocrypt or phallocarp traditionally worn by native male inhabitants of some (mainly highland) ethnic groups in Papua Province Indonesia and Papua New Guinea to cover their genitals.
They are normally made from a dried out gourd, Lagenaria siceraria, although other species, such as Nepenthes mirabilis, are also used. They are held in place by a small loop of fiber attached to the base of the koteka and placed around the scrotum. There is a secondary loop placed around the chest or abdomen and attached to the main body of the koteka.
Men choose kotekas similar to ones worn by other men in their cultural group. For example, Yali men favour a long, thin koteka, which helps hold up the multiple rattan hoops worn around their waist. Men from Tiom wear a double gourd, held up with a strip of cloth, and use the space between the two gourds for carrying small items such as money and tobacco. (wikipedia)
Yes, I think you can guess the purpose of the pumpkin.
The pumpkin is taken and cut off one end. After that the pumpkin meat is dredged until all its contents come out and leave a hole, so as to facilitate the entry of male genitals into Koteka.
After being dredged, Koteka will be heated on hot coals until it turns brown. Only after the pumpkin changes color is followed by a drying process that will take up to a day. If all processes have been passed, then the final stage is to put a rope on the pumpkin and wear