The Floating Gods (Viriconium #3)

Third book in the Viriconium sequence. The city is beset by a mysterious plague that affects the artists quarter and drains their vitality and hope. As artist Audsley King slowly dies from the plague, her friend Ashlyme tries to save her, and the result is at turns comic, tragic, and absurd. Much less fantastic in tone, it could be set in an alternate London.