Disclaimer: Delight, Delirium, and the Endless generally belong to Neil Gaiman and DC Comics. The sonnet form is public domain. The merging of the two concepts was my own idea.
Author's note: This poem is meant to deal only with the basic concept of Delight becoming Delirium. Concerning the details of the case, I confess I know nothing (having only read one Sandman book, Endless Nights), so criticism on those grounds will be somewhat beside the point.
"She is become Delirium," they say,
And seem to think that they have judged aright.
"She ever paints the world in blue and white,
When any fool can see the world is grey.
"Well, let her go, and let her laugh and play,
And revel in her poor, Delirious sight.
We know the truth – 'tis madness to Delight –
And so we walk her elder sister's way."
And yet I scan my planet's hills and vales,
And many quite Delightful things I see
Which do not seem Delirium's marks to bear.
Then is Delight Delirium? Can it be?
Perhaps there is an error in the tales –
For I find greater madness in Despair.