"Absolutely not! It's free coffee. And you're right, it does taste kinda gross if you let it sit." Though perhaps he should think about it twice before accepting coffee from a stranger. Ah, well, Flat knows he's done weirder and stupider risks than this. And if it's poisoned, then he'll simply live through it.

Besides, Flat can't see this as anything other than a chance to make a new friend. Even after so many things change, that one aspect of him will not. "By the way, sir, what's your name?"