This is how he figured it'd be. Sylar heaves a sigh, gearing himself up for this, before he reaches up and puts his hands on Al's shoulders.

"Alphonse Elric, look at me." He'll do his best to catch Al's gaze, even if the armour kid tries to look away. His own eyes are so bright they're almost manic, filled with fierce determination. "You're not going to believe me right now, but you need to hear it because it's the truth: You were absolutely worse off than me, during that whole thing. You had your self taken and twisted out of shape, until it would do things that are against your very core. And it wasn't even a fluke of genetics for you, someone specifically targeted your mind and forced it to their will. I don't have words for how terrible that is. It wasn't you. It felt like you, but it wasn't. It was awful and you are just as much of a victim, and I'm not gonna leave you alone in that."

'And you aren't going to take the excuse to leave me alone, either' is heavily thought but left unsaid. He can't lose Al to this. If he does, he has no hope for himself.