The bawdier the better. NSFW and possibly offensive.
I once knew Dwarf named Mary,
Whose chin was beautifully hairy.
Her long golden tresses
Hung down to her breastes,
And inside them there lived a fairy.
There once was a Mermaid named Jo
Who was more useful up top than below.
Her naughty bits
Stopped at her tits,
So she could only suck off a beau.