Love is sharper than stones or sticks;
Lone as the sea, and deeper blue;
Loud in the night as a clock that ticks;
Longer-lived than the Wandering Jew.
Show me a love was done and through,
Tell me a kiss escaped its debt!
Son, to your death you'll pay your due—
Women and elephants never forget.
Ever a man, alas, would mix,
Ever a man, heigh-ho, must woo;
So he's left in the world-old fix,
Thus is furthered the sale of rue.
Son, your chances are thin and few—
Won't you ponder, before you're set?
Shoot if you must, but hold in view
“Rue” of course means ‘Grief’ or ‘Sorrow’ (as in “rue the day!”), but the  plant  was long  used as a contraceptive  giving this line a potent double meaning. 

Ballade of Unfortunate Mammals