Like Gautier, Dore (1832-83) was a little before the time of Decadence, and never, to my knowledge, identified with it. But to me, his illustrations sum up the dark sensuality of the movement. Also, he was a total dandy. I mean, look at him:
I love how his fairy tale illustrations make obvious the underlying sexuality of the stories which had been supressed in the nineteenth-century.
He also illustrated an edition of the Bible, and it’s noticable that he chose the more decadent scenes to depict
His illustrations of Poe’s works are sensational
And he definitely brought out the darker side of Shakespeare.