“The religion of Christianity
Is mixed of sweetness and cruelty
Reject this Sweetness, for she wears
A smoky dress out of hell fires.”

Noir comme le diable, chaud comme l'enfer, pur comme un ange, doux comme l'amour.
frequently misattributed to Talleyrand, no primary source exists, its not his style of speech, and he famously drank tea not coffee.
Misattributed

"Sweet Little Sixteen" (1958)
Song lyrics

Source: Dictionary of Burning Words of Brilliant Writers (1895), P. 105.

Source: The Disreputable History of Frankie Landau-Banks

Source: Wolf at the Door

Original: (it) Se è carina, dolce ma stronza e complicata, è la donna di cui ti innamori.
Source: prevale.net

Peter Bell the Third http://www.gutenberg.org/etext/4697 (1819), Pt. III, st. 1

Source: Hamlet