All Arthur wanted to do after playing an exhausting game of football with his mates was take a nice refreshing shower and call it a day. So of course when he got home his flatmate Merlin would be hogging the shower all to himself.
Arthur kicked off his shoes and began pulling his shirt over his head as he walked to his room. He may not be able to bathe just yet but at least he could get out of his sweaty clothes. He spread out naked on his soft bed and cooled off while he waited for Merlin to finish. When ten minutes passed and Merlin was still in the shower, he got up angrily, wrapped a towel around his waist, and went off to ask what could possibly be taking him so long.
The closer he got to the door the more furious he became. Steam was coming through beneath the crack, and just who did Merlin think he was, using all the hot water like that? Arthur lost control of his patience.
"Merlin, get out before I throw you out!" Arthur yelled as he slammed the door open and pulled back the shower curtain. "Oh, bloody—"
Merlin had his forehead pressed against the tile wall with one hand fisting his cock and the other behind him fingering his arse. He jumped to hide himself, nearly slipping and falling when Arthur pulled the curtain back.
"Arthur!" Merlin shouted in surprise. "I'm taking a shower here!" His expression and tone were angry but the blush across his cheeks gave away his embarrassment.
Arthur was speechless for a moment, spending the time instead to take in Merlin's thin but (surprisingly) muscular body, dripping wet and flushed with arousal. His cock was pretty impressive as well, try as Merlin might to hide it.
"Arthur!" Merlin yelled again, and he snapped back to attention.
"No, you were taking a shower ten minutes ago. Now you're just wasting hot water."
Merlin glared at him for what felt like a thousand years and Arthur had to really try to keep his gaze from drifting south. Finally, Merlin yanked the curtain back into place and said, "God, you're intolerable. Just give me a couple minutes alright?"
Arthur would have walked right out and dealt with his own growing problem if it hadn't been for the fact that Merlin had called him intolerable.
Instead he pulled back the curtain yet again and stepped into shower, fully intending to push Merlin out.
"Oi!" Merlin complained when Arthur grabbed his arms. "What do you think you're doing?"
"I said get out or I'll throw you out, didn't I?"
"You can't just throw someone out of their own shower."
"You forget that I own half the shower."
"Then stay on your half, prat!"
They faced away from each other and crossed their arms over their chests like angry children. At some point during all the grappling and arguing Arthur had gotten fully erect and he could only hope that Merlin hadn't noticed. The fact that Merlin was only a few inches away and just as hard behind him certainly wasn't helping.
Finally, he sighed. "Get me a cloth then, will you?"
"Get it yourself," Merlin snapped back.
"Do you want me to stay on my half or not?" Though the truth of it was that he didn't dare risk bumping into Merlin in his current state.
Merlin groaned and reached behind the curtain for a clean cloth.
Arthur knew Merlin was waiting for him to turn around and grab the cloth from him. And he knew that Merlin was probably still achingly hard and annoyed with him. But he didn't know how this would end. When Arthur finished bathing, would Merlin just stay and finish himself off? That seemed somehow utterly ridiculous. How would Arthur get through this without touching himself even once? What had he been thinking, bursting in like that? Even if he did own half the shower, a man had a right to his privacy. But then Arthur didn't want an ice cold shower either...
Finally he turned around and said, "This is all your fault," before backing Merlin up against the wall and kissing the living daylights out of him.
To Arthur's (pleasant) surprise, Merlin didn't put up any resistance at all. In fact, the moment he caught wind of Arthur's intentions he gripped Arthur tighter, pulled him closer, and curled his fingers possessively in the blond hair.
When Arthur pulled away for breath, Merlin replied, "You're the one who barged in unannounced and demanded I get out." He pushed his hips forward and Arthur breathed in through his teeth at the contact of his dick against Merlin's.
"Well if you hadn't been taking forever, I wouldn't have had to barge in." Arthur fought to stay coherent but Merlin wasn't making it easy. It seemed as if he was punishing him for interrupting his wank earlier, and dammit if it didn't drive Arthur mad with lust.
Arthur pressed his lips against Merlin's again, less urgently than before but with the same amount of passion and desire. It was mostly to keep him from saying anything else. At least that's what Arthur told himself.
Merlin had other ideas. He slid his hands down to rest on Arthur's waist, and when Arthur moved to claim his neck, Merlin brought his hands around and gripped Arthur's arse, bringing their bodies together like lock and key.
The resulting friction between their cocks drove Arthur nearly to the brink and he pulled away for fear of coming too soon. He opted instead for wrapping his fingers around Merlin's flushed erection and pleasing him with long, hard strokes.
The warm water from the shower made the air foggy with steam but also threw everything into a sharp focus, like walking outside at dawn and seeing the tiny drops of dew on the grass. It heightened their sense of touch and the smell of sex was much stronger. All this, plus the fact that he'd already been close before Arthur interrupted him, brought Merlin off in no time with Arthur's name on his lips.
He came hard, strings of spunk shooting nearly a foot into the air out of his throbbing cock. Arthur thrust himself against Merlin with reckless abandon, not caring that the white hot mess got all over him. Soon Merlin would be covered as well, and that thought alone, of his seed dripping down Merlin's chest, took him over the edge.
The smell of sex was even thicker than before as the water washed away evidence of their orgasms. Still, they just stood, holding each other while they caught their breath and trying to make sense of how their situation went from zero to a hundred so quickly.
Arthur broke the silence first. "I suppose I better do some actual washing before we really do use all the hot water."
Merlin bit his cheeks to stifle a huge smile at hearing Arthur's use of the word "we" as Arthur picked up the cloth from the floor of the shower and reached behind him for the soap. He was about to leave Arthur to it, when Arthur grabbed his wrist and stopped him.
"Stay," he said. Merlin's confused expression threw Arthur into a momentary panic and he searched for a reason why exactly Merlin should stay. "I need you to wash my back."
Arthur handed the soapy cloth back to Merlin and turned around. Now that he wasn't facing him Merlin didn't hide the stupid grin that stretched across his face as he rubbed Arthur up and down. Little did he know that Arthur was smiling just as wide.