Go forth at nightfall crying like a cat,
Leaving the lofty tower I laboured at
For birds to foul and boys and girls to vex
With tittering chalk; and you, and the long necks
Of neighbours sitting where their mothers sat
Are well aware of shadowy this and that
In me, that's neither noble nor complex.
Such as I am, however, I have brought
To what it is, this tower; it is my own;
Though it was reared To Beauty, it was wrought
From what I had to build with: honest bone
Is there, and anguish; pride; and burning thought;
And lust is there, and nights not spent alone.
A clever ending line. She leaves off the “lust” and “sex” parts of what goes into the poetry till the last line, revealing with a suggestive “nights not spent alone” a forthcoming truth: that living a promiscuous, sexual life directly helped make her good poems as good as they are. Other poets might say that God, or hard work, or capital-B Beauty inspire them, but Millay says straight up that her poetry comes from smutty lust and romance. 
 As  plenty  of  people  have observed, Millay’s sonnets often deal with romance, sex, sexuality and so forth. Her public image had the same themes to it. This made her tremendously popular with young people in the 1920s, when Millay was something of a sex symbol. It’s also to blame for her waning popularity in the decades after her death, as people started to look for more serious, intellectual and restrained female poets like Plath and Bishop. 
 What do you think? Overrated sex symbol, or brilliant poet? 
 
 As you can tell by the perfectly exquisite structure of this sonnet, Millay wasn’t an idiot. She was a good, some might say extraordinary poet. Like many women who rose to fame in that half of the century, Millay’s name will always contend with gender stereotypes about intelligence and ineradicable associations with sex and “un-seriousness”. So be it. This poem, and others, will stand to tell otherwise. 
 Note:  J.D. McClatchy  goes into this stuff in much more detail in his review.
I Too Beneath Your Moon Almighty Sex