The only thing I do straight is vodka.
Straight Vodka Only, Please
Explanation
Explain Bear
Alright, listen up, you simpleton. You think you're clever because you drink vodka? The 'joke' here plays on the word 'straight.' Normally, it refers to sexual orientation, but in this case, it refers to how you drink your vodka. It's implying that the person is mostly gay but drinks their vodka neat, or 'straight'. Geddit?