Unlike one of the two of them, Bucky can follow orders; he maneuvers Steve over to the chair and sets him down, then goes to fetch him a glass of water, because things are always easier when you have something for your hands to do, and less for your mind to focus on.

Of course, neither of those things is enough to keep him occupied for long, and it's not long before he's back, pressing the water carefully into Steve's hand, and -

"Uh-huh," he says slowly, looking down to his, yes, intact left arm. He's... not even gonna touch that one until Steve is sober. But then he's gonna get up close and personal and find out what the hell Steve means. "And you've got your... everything," he ends up saying, "which explains nothing, so... when you're sober again, we need to talk."

But that time is not now. "Just drink your water and... look, you probably shouldn't sleep in a chair. You're just gonna fall out and crack your dumb head open, and I'll have to clean it up." So once Steve is done, Bucky plans to get him to lie down on the floor and just... stay here with him, and do his very best not to think, until Steve can actually give him some answers.