[He doesn't respond for a long time. There's something cyclical here. He shouldn't have lied to Arthur for years, but he didn't have a choice; he shouldn't have stripped Arthur of all sense of feeling as if he was Camelot's protector, but if he hadn't intervened the way he had then Arthur would be dead and Camelot fallen.
There's only so bad he can feel about keeping Arthur alive for long enough to realise his destiny. Apparently there's no bottom to how bad he can feel for deceiving his best friend.
Eventually he says two words and the inner door opens an inch, and if you really want to Charles you can come and see Merlin's little cupboard room and tiny awful bed.]
[Spam]
There's only so bad he can feel about keeping Arthur alive for long enough to realise his destiny. Apparently there's no bottom to how bad he can feel for deceiving his best friend.
Eventually he says two words and the inner door opens an inch, and if you really want to Charles you can come and see Merlin's little cupboard room and tiny awful bed.]