Something similar is happening to me. My main character is a mage & he has black drops falling bouncing off of him. He doesn't seem to have any status afflictions, nor does it seem to be any armor weapon effects. Can't figure out what it is.
A handful of my characters have been glowing with either some Red or Purpleish Aura out of no where off and on for the last like 15 or so hours. And it it only seems to disappear for a time during only specific cut-scenes at various points in the game
So yeah. I don't even pay much attention to it anymore.
And as far as i am concerned. They are permanently on fire but they simply don't give a damn.