I'd rather kiss a mad cow on the muzzle than a smoker on the mouth.

The line uses grotesque hyperbole to express intense disgust at kissing someone who smokes. By comparing a smoker’s mouth to the muzzle of a “mad cow” (a deliberately extreme, disease-tinged image), the speaker frames tobacco breath and residue as not merely unpleasant but viscerally contaminating. The joke depends on shock value and on a cultural association between smoking and stale odor, poor taste, and health risk; it also hints at shifting social norms in which smoking becomes a stigmatized habit affecting intimacy. As a quotation, it functions less as a reasoned argument than as a memorable, comic one-liner meant to shame or deter smoking through revulsion.