Castiel doesn't have to touch Dean to heal and cleanse him. He's an
angel, no, he's a freaking angel, and he could heal
Dean from the other side of the planet. They share a bond.
But he's just watched Dean arch, teeth gritted on a moan, and he's
feeling unsettled. Dean's blood smells wrong. He needs to grip Dean's
shoulder, just like when he tore Dean free of hell.
He wishes he could leave a mark again to help Dean remember him with
gratitude when everything changes between them, as it will.
God knows, bonds can break.
Angels do, too.