"John, I'm back," Sherlock announced as he stepped through the door to 221B. He stopped dead when he saw the raven-haired god lying across his couch. "Loki." He murmured, "I suppose you're not here to apologise." Sherlock rolled his eyes. The god ignored him. They had had a fight earlier that week when John discovered them, and Loki refused to apologise. Sherlock, of course, was too stubborn to apologise too. "It's more comfortable here. Plus I have nowhere to stay." Loki muttered defiantly. Sherlock went over to the couch opposite him and lay down, facing the back of the couch. He closed his eyes. At that moment, Mrs Hudson walked in. "Sherlock, who's this? One of your customers?" she asked smiling at Loki, who was now sitting up. Sherlock sighed. "Yes, I suppose he is." Loki didn't look very happy about that.
"Oh, so that's what I'm reduced to. A 'customer'," he grumbled. Mrs Hudson looked at the two men with confusion. "Sherlock is everything ok?" she asked but Sherlock just waved her away.
"Yes, yes Mrs Hudson. Now go away."
Loki smirked at that. Sherlock was still lying with his face in the couch cushions and his back to Loki. Loki teleported next to him and leaned against the couch. "No need to be grumpy, you know." He said quietly as he stroked Sherlock's hair. Sherlock grumbled in protest, but Loki ignored him. "Come on stop being a grouch! You're so boring right now!" Loki complained childishly. Sherlock turned to face him, his eyes filled with anger and annoyance.
"I assure you that I am not boring."
"Yes you are."
"TAKE THAT BACK!" Sherlock picked up his gun and aimed it at Loki. Loki, who of course had been smirking the whole time, sobered up a little.

John heard shots go off in the apartment he shared with Sherlock. He didn't worry too much – it would just be Sherlock being bored again. When he opened the apartment door he froze, his eyes wide with shock. Locky, or whatever his name was, was standing casually in the apartment, on the other end of Sherlock's gun. His expression was anything but casual, though. It was filled with anger and outrage. "DID YOU JUST SHOOT AT ME?" he shouted.
"Nope," replied Sherlock, shooting again. Loki disappeared, narrowly dodging the bullet, and reappeared behind Sherlock. He grabbed the gun and wrenched it from his grip before he could react. "Is uhh, this a bad time, then?" John asked awkwardly. Both men turned to look at him. John backed away slowly, as if concerned about threatening dangerous animals. "I'll just uh, go then." he said, turning towards the door. He left just as quickly as he arrived.

When he returned, Sherlock was playing violin. "I'm guessing the irritating twat has left." John said cautiously as he stepped into the living room.
"Yes, he did actually, but I believe he just returned," came Loki's smooth voice from one of the couches. John groaned. Having one arrogant madman was bad enough. Two was definitely more than anyone could handle. "Right, so I'm just going to go to my room," he announced, walking away. Sherlock still hadn't looked up from playing his violin. As he passed, John saw Loki was lying on the couch reading, but seemingly disinterested in the book. He heard Loki mutter something that sounded like, "asshole," as he passed by. Whatever. At least they weren't fighting now.