I think Raphael works for Asmodeus, as there is a book in the EA titled "The Devil you know" and it's about Asmodeus.
He clearly wants something (beyond your soul), both Gale and Shadowheart suggest he wants something from you.
He send someone to keep you alive on a certain "cure the tadpole" path, but he doesn't want to do his deal yet for some reasons. Looks like he is waiting for you to reach a certain point/place (Moonrise Tower?) before doing so.
I think he needs you to do something for him in the real world, but actually has nothing to deal in exchange so he's just waiting for you to have exhausted all cure options before he can force you to do it.
