In all actuality, Barnaby really does hate fires.
This includes fireplaces. Real, burning ones especially – they make him nervous, even when he knows they're being carefully tended, even when he knows he can outrun any fire that might spread accidentally from them.
Still – at Kotetsu's side, it's a little more palatable. The man himself is warm and the fire is sort of nice, low-burning and mostly sparking embers. Kotetsu's hands are in his hair, stroking through it and down his back, his lips on his neck – the scratch of his beard a familiar, welcomed thing that makes Barnaby shiver.
No, not a bad way to spend a cold day at all. Wrapped up in everything that is Kotetsu, especially when Kotetsu leans back, drags Barnaby on top of him, kissing and urging him. Barnaby's eager, then, sweat rolling down the back of his neck from heat and strain that has nothing to do with a fear of flames – no, it's from a far more carnal variety, one that brings him to grab Kotetsu's hips, to drag him closer, to thrust harder into him and to kiss and bite at the other man's lips as he gasps and comes inside of him, everything else forgotten but Kotetsu.
Kotetsu is ever a balm to his nerves – in many and all things.