On posters for Blue Valentine and The Notebook, he seized Michelle Williams and Rachel McAdams and strategically attempted to swallow their faces, merely to create a plausible excuse for keeping his left cheek shrouded in mystery.
The Weinstein Company, New Line Cinema
"Yes, that was the only reason."
Based on this overwhelming evidence, we are left to conclude that Ryan Gosling, in a last-minute act of panicked desperation, caved in the left side of his face on the poster for Only God Forgives:
He is now seated by the right face of the Father. Amen.