So, can we just talk about that gif for a moment? I’m not really good with metas, but I’m going to try my best.
What I find interesting about that shot is how Killian, the Charmings, Henry, Belle & Rumple and Elsa are positioned. We have Belle, Rumple and Elsa in the back, because they are not as ‘close’ to Emma as the others (obviously) - but Elsa is still positioned in front of Rumple, because she’s grown to be a friend of Emma’s. Then we have the Charmings, then Henry and finally Killian in the front. I think that the way they’re positioned in that shot reflects how ‘close’ they are to Emma, relationship-wise, in their current situation. Now don’t get me wrong, I’m not saying her relationship with Killian is more important or stronger than her relationship with her son and her parents, BUT I do think that Killian is the only one who’ll be able to help her, because he can relate to her and understand her. There are a lot of parallels between 4x04, when Killian lost his control and thought his hand was cursed and Emma in 4x07 and that can’t be a coincidence.
Of course Elsa is the one who understands her best (in her situation), but Elsa and Emma haven’t known each other that long and Elsa has already enough problems on her own plate.
David and Snow have been more concerned with little Neal lately and are still really insecure about their job as parents, so it’s hard for them to find a way to get to Emma and to understand her completely. Snow has literally “failed” in that scene (and the scene before with the baby), because she hasn’t been sensitive or understanding at all. She’s been more concerned about David and Neal than Emma and that’s why she’s positioned in the middle. David is with her, because he always is and because I think even though he’s trying, he also has a hard time to understand Emma. They love her, but they can’t help being a bit afraid of and irritated by her powers.
Then there’s Henry. He seems a bit closer than the Charmings, because he still believes in her and he loves her, but he’s just too young and too unexpierenced to be really able to help her here. It’d be too much for him to handle and I think we’ll see that in the next episode.
Now let me get back to Killian. I think it’s even more obvious now why he’s positioned in the front here. He loves Emma unconditionally and he’s not scared of her whatsoever, because he’s (basically) the same. He knows what it’s like to feel like a monster, to feel unloved and like an outcast. He knows what it’s like to lose control. More than that, he’s truly concerned about her and only her. There’s no one else for him. And he would never, ever give up on her - he doesn’t even care if she hurts him, for god’s sake! That’s why I think he will be the key to everything in that story arc. He’s a threat to the Snow Queen, because he would never give up on Emma and he’s the most important person to Emma, because he’s the only one who can help her. We all know by now that Emma let her walls down for him, she let him in and she loves him back, even though she might not have realized it yet (or maybe she has; judging by the way she looked after their date; but she’s certainly not ready to admit it). Right now, he’s the closest person to Emma, physically as well as emotionally.