His dark green rubbery skin was thick enough for him to play the game of Vogon Civil Service politics, and play it well, and waterproof enough for him to survive indefinitely at sea depths of up to a thousand feet with no ill effects.

Mr. L. Prosser was, as they say, only human. In other words he was a carbon-based life form descended from an ape

something like these, perhaps? There are probably better examples, I just skimmed through the first couple chapters of Hitchiker's Guide to the galaxy

Well, in the first bit of the Hitchhiker's guide, there's:

“You’d better be prepared for the jump into hyperspace. It’s unpleasantly like being drunk.”

“What’s so unpleasant about being drunk?”

“You ask a glass of water.”

Which does fit, even if it's not necessarily a "well-known phrase"