I Saw the Ugliest Woman is a country and western song sung by Roger in his persona of Cuss Mustard when inspired by an ugly neighbor of his ex-wife Naydern when he fakes spousal abuse to get out of the marriage in "Gorillas in the Mist".
Roger: I saw the ugliest woman I ever did saw
Face like a turnip and an under-bit jaw
Audience member #1: Yeah, tell it like it is!
Roger: Inbred from inbreds then inbred again
If ugly was pretty then she'd be a ten
Audience member #2: That sounds just like my wife!
Roger: She was so damn ugly
So I got drunk and fucked her in my truck