[ part of that last kiss is to conceal his own embarrassment, because man, he feels like awkward about jumping to conclusions. Not the biggest ones, though, considering they were discussing it literally only so many moments earlier. Then they were suddenly confessing, and now... Suddenly it dawns on him this is basically the most backwards situation ever, and he can't help but laugh quietly at it, realizing he doesn't care if it's weird. He never cared about rules anyway, and this suits them somehow. ]

I missed you, too. This is .. basically the weirdest thing that's ever happened to me. My little sister found me all the way across the universe, and then I find out one of my closest friends is still here after all, and we're really going for this? I don't even remember the last time I was this happy.

[ Sure, there's some really horrible stuff going on right now, but he doesn't want to let that wash out the good things. Why save the universe if he can't even save himself? Seems stupid to deny the good things just because there's death and evil out there. ]

Maybe you should throw me over your shoulder like a caveman and take me back to your room.

[ he definitely can't let Shiro say something like that without making fun of him, even if it comes a little late. ]