[John leans over and returns the fist bump as soon as possible. You don't just leave a friend hanging like that.]

I think the weirdest thing will just be seeing Karkat acting nice to anybody. I will not believe that is possible until I see it!

[Okay, also it will just be weird to see him and Dave holding hands, but this doesn't seem like the kind of thing John should be ribbing his best bro about. At least not yet. He's got to get used to it first before he can start friendly, obnoxious teasing about it.]