Merlin had been in Camelot's dungeon plenty of times before, both as a 'guest' and as a visitor, so he was pretty familiar with the various cells.

Arthur must be especially annoyed this time because the guards put him in the farthest cell.
None of the cells were nice, but this one was particularly bad.

It was the coldest cell for one thing, especially since it had no blanket- something that wasn't too surprising since it also had no bed.
In fact all it had was a bit of straw (and that was a new addition since the last time he'd been here).

Sighing to himself, Merlin gathered the meager bedding and settled in for a well-deserved rest.
In a stroke of (what he considered to be) genius he created a pillow by removing his neckerchief, folding it in half, and filling it with straw.
Normally he would have just used his jacket, but that was needed to compensate for the lack of blanket.

Face buried in his makeshift pillow, Merlin inhaled the scent of the fabric and its stuffing.

This specific neckerchief had been given him by his mother fairly recently and it still held a hint of her scent.
Nostalgia overcame him and he grinned.

Sleeping on the floor with only a bit of straw, Hunith's soothingly earthy aroma wafting into his nose, Merlin drifted off with a gently smiling face that belonged to a much younger version of himself.

When Arthur came to fetch him the next morning he was still sleeping happily.

Even after the king's surly "Wake up, Merlin" his only reply was "Five more minutes, mother" as he buried his face further into the blue cloth.