John woke to an unusual sound-no music coming from Sherlock's room. He was playing the violin, obvious, but he wasn't playing the usual classical, waltz, or just random bits of music from one to another that usually woke him. A little annoyed at being woken up from his sleep but also a bit curious, John went down the stairs tentatively. Thankfully whatever it was that Sherlock was playing was quieter than the typical volume that Sherlock liked to play his violin at. Just a few steps from Sherlock’s door John could tell that the music was more in a song structure, and one that John was semi-familiar. It sounded like a popular song that he had heard on the radio a few times. What caught his attention and brought up the familiarity was what he recognized to be the chorus. In trying to recall the words he remembered that it had something to do with love, but then almost every popular song did; so that didn’t help much. Unfortunately the melody was taking on a different tune of sorts. It was slower than the previous parts of the song that John had heard, but then went back to the previous pace. What was that part of the song called? A bridge? Yeah, he was pretty sure that was what it’s called. John learned forward a bit in order to hear better as it had quieted down in the room inside the door for a moment, but straighten back up when the set volume returned. By now John could hear the words in his head a little better now. It went something like this; 'Love is ... drug.' Which definitely wasn't like Sherlock at all. John knocked on Sherlock's bedroom door. The violin went quiet, and then there was some shuffling as Sherlock made his way to the door. The door opened and John was left looking at a disgruntled flatmate.
"Aren't you supposed to be sleeping?" Sherlock questioned irritably.
"I was until you started playing. What song was that Sherlock?"
"You usually stay in your room when I play at night."
"I do, usually. But you normally don't play popular songs, you know like the ones that young people like."
"And what's wrong with that?"
"No-nothings wrong with it, it's just not what you usually play." When Sherlock started to open his mouth to snap back a reply John quickly interrupted, "Now stop going onto tangents Sherlock! What were you playing?”
"Why do you feel the need to know?" Sherlock said a bit defensively.
"Because it's a little obvious that you don't want to tell me."
“And I'm not going to tell you; but if you want I suppose you can try to guess since you recognize it." Sherlock went back inside his room and grabbed his violin. Together they went to the living room where John sat down and Sherlock stood in his usual place by the window to play. John closed his eyes as Sherlock played the violin. When Sherlock got to the second verse he sped up near the end, but other than that, it was the same as before he had knocked on Sherlock's door. John closed his eyes and started humming along with the chorus. The chorus played longer than it had in Sherlock’s room which then lead into a new part that John hadn't heard; but then that was probably because he had interrupted Sherlock right before he could continue. There was a little bit a plucking like sound coming from violin, but the bow was still moving. Sherlock finished with a flourish. He turned to face John and asked, "Do you have an answer?"
"Um, no. But I might if you play it again?"
"Fine." Sherlock replied with a roll of the eyes. Sherlock ended up replaying the song several times before John was ready with an answer. ”Shall I play it again or do you finally have an answer?"
"I have one." John replied.
"Finally." Sherlock groaned. "Well what is it?"
"It's called 'Your Love is my Drug'... by Ke$ha? Am I right?"
"Very good John, you got it."
"Why were you playing it?"
"Because I felt like it, why else!" Sherlock answered throwing his hands in the air.
"Yes, but why did you feel like it?" Sherlock started walking to his bedroom while answering. "It's a message John," He drawled, "for all of those idiotic people we hang out with." And then promptly shut the door. John sat there for a minute taking in what Sherlock had said. If he got what Sherlock was saying right, that meant that all of the love that Mrs. Hudson, Lestrade, Molly, and himself gave Sherlock was, addicting like a drug? John decided that he needed to sleep on that.