Never Let Me Go
Sometimes, he thought he should give something to Merlin, something that made it clear how much he mattered. It seemed, also, a foolish thing to do, the kind of thing a man does when he's wooing a woman. And, of course, Merlin wasn't a woman. He was well aware of that.
(Painfully so.)
When he tried to figure out what could possibly represent his friend, Arthur always came back to this drawing he saw in one of Gaius books when he was a child – one he was almost sure Gaius shouldn't have kept – of a golden flower, and its petals glowed even in the faded ink. It wasn't the prettiest one he had ever seen, it even looked a bit clumsy, but there was such a feeling of nobility in its shapes, at the same time strong and humble, majestic and ordinary, that most nobleman wouldn't manage to acquire in a lifetime.
(But, of course, he couldn't give Merlin a flower. Maybe he should give Gwen one, instead.)
He tried forgetting about presents, since he couldn't imagine what in the world would be both appropriate and worth of Merlin. He wasn't a man for fancy things, of battle gear – he wasn't a easy man to please with obvious man-stuff. So, it would be better to think of words. Saying something, making it clear that there was no one Arthur wanted around more or trusted more than his foolish servant.
(He was always awful with words when it came to feelings, he only knew about motivational pre-battle speeches.)
So he sticked to gestures. Nothing too grand, for he wouldn't want to scare him away or make the whole of the kingdom aware of the feelings he hid deep inside. It was all long looks, and open smiles, and those came easily, for he was always happy whenever around Merlin. He hoped that it would be enough; he hoped that it would make him see those things he could not say, of even feel. He hoped that it would be the same for him.
(And when Merlin smiled back, the biggest grin in the world, he felt like he had been swept off his feet.)
Arthur wanted Merlin to be around forever. He wanted them to grow old together, sharing the burdens and the joy alike. He wanted it to never end, for nothing could break them apart, not Morgana's magic, nor his marriage, nor the wars. There were no secrets between them.
Or so he thought.
(Which made everything much harder in the end.)