If you love dark visual novels, then it might be worth checking out Sanator: Scarlet Scarf. This upcoming title puts players behind the mask of a plague doctor named Richard.
His city is dying. The grim atmosphere is a perfect setting for a dark fantasy tale to take place. Curious to know more? There is a free demo available right now.
This demo, Sanator: Chronicles of Reustadt, is actually its own stand alone story. It should provide a good feel for the story and tone of the full game. The demo is available on Steam for Windows, Mac and Linux.