Steve was on his way up to his quarters when he was informed by JARVIS that Mr Stark was up in the labs and possibly required his assistance. Sighing, he looped his towel around his neck and went up another level, hoping whatever Stark required assistance for wouldn't take long. Unfortunately, this wasn't the case.
It seemed Tony had gotten bored and decided to work on his Iron Man after all, accompanied by the appropriately loud music and a bottle of scotch. The combination of delicate machinery, tools and alcohol had gone together as well as could be expected.
"Tony, you're bleeding!" He kneeled beside the intoxicated inventor and grabbed at the man's arm, pulling it closer to examine the gushing wound.
"No, really? Am I? Didn't notice," Tony slurred, staring up at Steve with a clumsy approximation to a grin. "Look, Cap!" He smeared a little blood over his eyelid and pointed. "Red, white and blue!"
"Tony, stop. You're drunk. Keep still, please. I'm calling Bruce."
He shook his head furiously, pulling away and spilling blood over both himself and Steve. "I'm fine, Stevie. S'just a scratch."
It was not just a scratch. It was quite a bit deeper, and more bloody, than just a scratch. It seemed to have been caused by a saw resting nearby - what Tony could have been using it for he wasn't quite sure. As he folded his towel and pressed it into the wound, he wondered for the billionth time since coming to live at Stark Tower if Tony Stark was his own, personal punishment. As Tony went to take another swig from the near-empty bottle beside him, Steve tore it from his hands and placed it on the bench above them. By now he was used to drunken antics, but he hadn't seen Tony like this in quite a while. "Jarvis, get Natasha, please."
Certainly, sir. The AI was prompt at summoning Natasha, who stalked into the labs with the fury of an oncoming storm. She had been enjoying her night with Barton. After the stupid Bond movie they'd found something decent to watch and were having their first real night of downtime in months. She was beginning to suspect Stark was out to ruin it on purpose. Not even the sight of his bloody arm was enough to make her relent in her glare, or lighten her tone. "What did you do?"
"I was working on the armour...and then I got a saw out to test its invulnerability." Tony was fairly articulate, though stupid, for a drunk. He was still giving the two of them his lopsided smile and disliked it greatly when Natasha slapped him across the back of the head.
"Are you fucking kidding me, Stark? Steve, go and get the first aid kit, it's under that sink. I'll stitch him up and you can dump him in bed to sleep this off. The blood can be cleaned up in the morning." She ignored Tony's protests as she stitched up the wound and dressed it, barking at him to keep still. He did so reluctantly and was unwilling to move from the floor when she was done, so Steve scooped him up like a child and carried him to his room. Natasha followed them, only to make sure he actually got there; it wasn't unlike Stark to very smoothly talk his way out of a situation. She threw the glass bottle into a nearby trash can on her way out and requested JARVIS to lock the labs if Tony tried to come back for any reason.
"Thanks mommy. Don't tell Pepper." Stark was smirking as he got deposited rather ungraciously onto his bed by Steve, with Natasha glaring at him from the doorway. Tony had been becoming increasingly stupid since the Chitauri attack, and spent more time in a drunken stupor than could possibly be healthy. She knew the bottle of scotch was nowhere near all he'd drunk that day, but she and Steve both continued to delude themselves that this was nothing more than a onetime incident. Her tone was frosty as she went to leave the room.
"Goodnight, Stark."
As she and Steve made their way back downstairs - her to Clint and the movies awaiting them, he to his room - he turned to her with a frown. She shook her head before he could speak and quietly told him to leave it for now. It could be dealt with in the morning.