[He's slightly perturbed by the fact that he's struggling to picture Feferi making her way over in his mind's eye, but, well, he's new at being blind, maybe not being able to remember what people look like is a thing. He's too relieved to hear her getting nearer to be bothered too much.]

God, I'm so glad to s... Hear you. I guess. [his smile doesn't really falter, though! He moves closer to her than she's probably getting to him, and if he's a little hesitant when he reaches for her hand the only reason is that he isn't sure at all where her hand is.] Do you know what's going on, is this a dream bubble? [He is doubting this possibility more and more, but it still seems more reasonable than anything else he can think of.]