Who is Khamel from The Pelican Brief and what is their importance?

Khamel is the novel's most enigmatic character, Khamel, at 40-45 years old, can kill with anything, speaks 12 languages, and is considered the most proficient and expensive assassin in the world, demanding $10-$20 million per job. He is currently under contract to the reclusive oil baron Victor Mattiese and being locally handled by attorney Edwin Sneller. Khamel is wanted in nine countries. Among his most famous jobs since beginning killing at age 15 are the British ambassador to Nigeria, 17 Israeli soldiers on the West Bank in 1990, a German banker and his family in 1985, and a 1981 attempt on the Pope.