Ok no but you know what Merlin said about whispering complaints into his ear?
Imagine if it’s actually something Merlin always says when a recruit/technician/whatever would talk shit at him and that would usually stop them dead on their track and of fucking course no one would actually go closer to Merlin and they would feel properly chastised and ashamed of not having the balls to do so.
But thing is, as soon as he starts saying his by now oh so familiar line, Merlin knows, he just knows that Eggsy won’t step down from what is clearly a challenge. And well even if the boy does need to get that chip off his shoulder, Merlin cannot say he’s not in some kind of weird admiration over the fact Eggsy is the first one ever who refuse to submit to him.
And like just imagine afterwards, everytime Eggsy wants to call Merlin on his shit, he actually goes right up to him and does exactly as the man had told him, actually whispers how bloody stupid/ridiculous/whatever Merlin’s currently being at the time. And it’s one of the main reason he gains the respect of the others Knights so quickly because, while they’re not afraid of Merlin per say (they totally are), someone willing to go and essentially piss off the man while in stabbing distance is incredibly ballsy.
(But Eggsy knows no harms will ever come to him from Merlin, as soon as the man had deploy his ‘chute that day after the sky diving test. He might exasperate him to no end, but Merlin would be hard pressed to deny the fondness he feels for him. Because thing is about being at whispering distance? It allows you a pretty good look into someone’s eyes too.)
(And I imagine their first kiss happens a bit that way: Merlin is being his usual frustrating dick self and Eggsy is fed up and goes to him to tell him exactly what he thinks of him, but he’s suddenly stricken by the fact that even if he kind of want to punch him in his smug face, he’d rather just kiss the smugness right out of him. And those around them who see Eggsy freeze thinks that this is it, Merlin’s gone too far and Eggsy will finally snap and he might get a hit in, but Merlin will probably clean the floor with him. So they’re kind of in for a surprise when Eggsy decides that yes, he’ll indeed try to kiss the smugness right out of Merlin.
Turns out it’s really satisfying to be the cause of Merlin’s shocked expression.
But not as satisfying as it is to be kisses right back once Merlin processes what happened.)