Mouzafer is the "ruggedly handsome" (2.25) Balti porter who offers to carry Mortenson's packs for the very low price of four dollars a day. Mortenson later hires him to help with the building of the schools. While the Balti has a "taciturn suspicion of outsiders" (2.23), Mouzafer is gregarious and outgoing, serving as a bridge between cultures. Mouzafer isn't just a porter of the mountain, he's a porter of life, "helping to guide [Mortenson] past the roadblocks of life in northern Pakistan" (3.8). So, you know, thank goodness for this guy.
Basically, he's the Tenzing Norgay to Mortenson's Edmund Hillary, or, in non-mountain-climber speak, the Robin to his Batman. And in some instances, it might be the other way around, because without Mouzafer's influence, Mortenson might not have gotten anywhere. He's like a local celebrity, "well known throughout the Karakoram" (3.7), and his presence helps Mortenson meet people that he otherwise wouldn't if he were just a giant white man wandering the mountains by himself.