Randal "Randy" Marsh is Stan's father and as a geologist he's surprisingly involved in a lot of the plotlines in South Park.   Randy has also been revealed to have a decent singing voice, having been involved in a boy band as a kid, and knows how to play the guitar.

Randy Marsh Quotes

Butterflies have no concern for such things. Now I'm gonna go find myself some butterfly poon.

Randy

Randy: How does it feel to be a hundred and two, Paps?
Grandpa: Shoot me!
Sharon: Make a wish, Grandpa...
Grandpa: I wish I were dead!
Randy: That's our silly Grandpa!
Grandpa: I'm not kidding, God Dammit! I really want to die!

South Park Quotes

Cartman: I'll make you eat your parents.
Ms. Choksondik: What did you say?
Cartman: Nothing

Somebody who would have sex with Kyle's mom would have sex with just about anything!

Stephen Stotch