I cannot for the life of me remember the name of the book. I feel it was like something about a painted man, but I know it starts with a tattoo artist who unknowingly inks out a sigil that summons a demon, and is then saved by a blind lady with a katana, who might be called Winter. At some point he is granted "the Sight" and can now see the real versions of the people around him, some of whom are missing eyes, or ears, or have other horrid wounds that are the result of unpaid debts to supernatural beings.
He then goes on some big journey to the underworld, or some other secret realm, where angels and demons fly around in airships shooting at each other, and then at one point he fought a clone of himself. I think his mission might have had something to do with a book that he was supposed to give to the devil, but I could be pulling that from a different book.
I know for sure that he was a tattoo artist, that he got the sight, there was a blind swords lady, and that there were angels in airships.