Castiel would heard him coming, even if he hadn't had the angelic senses informing him of the youngest Winchester's proximity. He closed his eyes with a heavy sigh before steeling himself. Standing, he walked out without a word or a look at Ruby, reaching the door to the apartment before Ben did.
"Ben," he spoke calmly, gently, knowing what he wanted to do and honestly not blaming him for it. "You don't want to do this."
He stood in the doorway, between Ben and his target, all of his focus on the boy. "You shouldn't be here."