Cliff is the son of a Plant engineer who purchased land with copious amounts of water on it and as a result, makes a good living selling water to the town. He portrays himself at first as a kind, caring older man with a sense of humor who only wants to protect the water and his guest Marianne. He even hires Vash as bodyguard to help.
Appears in episode 2.
(Source: Trigun Wikia)