Who is Tukten from The Snow Leopard and what is their importance?

Tukten is one of the porters that accompanied Matthiessen and Schaller on the trip. Tukten is a mysterious man who seems to have a fluctuating personality and is deemed suspicious by the other porters and the senior sherpas. However, Tukten proves himself to the party and becomes head sherpa, remaining on the dangerous journey until the end.