Kotetsu knows, from the moment he feels Barnaby's glare, that he should havelearned.
Barnaby gives him a number of chances with things that irritate him, but he's sure at this point, he's used up every chance when it comes to this. And by this, he means something as simple as brushing his teeth in the shower, just like healways has – but of course, Barnaby finds it irritating and all sorts of off-the-charts wrong.
So this happens.
Barnaby's in the shower with him, hair dripping and plastered to his neck and shoulders from the steady beat of hot water. His lips are on Kotetsu's neck, biting, snapping against the skin to methodically bruise and mark and he's snatching the toothbrush from Kotetsu's hands, tossing it aside and onto the tiled floor beyond no matter Kotetsu's protests.
What are protests, though, when Barnaby's kissing him, wrapping his hands up into his hair, a groan rumbling in the back of the blond's throat when the lingering taste of toothpaste tingles on his tongue? His back hits the cool tile wall of the shower and Kotetsu hisses, arches, growling at the connection of their bodies, slick and hot and that is enough to make him reach out, grasp at Barnaby's back, raking short nails down his spine and pull him closer.
Barnaby doesn't let him, though. His hands slip down to Kotetsu's shoulders, firmly pushing, coaxing him down, and he only says one thing: "There's something else to put in your mouth now."
A wry smirk tugs at Kotetsu's lips. "Jesus, Bunny, isn't this messier than me brushing my teeth?"
"Where's your mind at, old man?"
Barnaby leans to the side, plucks up something Kotetsu didn't notice he had brought with him and set on the edge of the bath, and calmly thrusts it perhaps and inch or two from the older man's face.
It's a container of floss.
"Something you always forget," Bunny deadpans, "flossing."
Kotetsu reminds himself, as Barnaby calmly sets the container of floss on top of his head and then exits the shower without a word, that his boyfriend is pure fucking evil at times.