The case went much too quickly. Between you and Sherlock throwing deductions out like a gun with bullets, it was obvious the butcher down the street did it. Donovan and Anderson had nearly blown a fuse to find there were two now, but Lestrade liked it. You were kinder and less callous than Sherlock, and actually told him how to get the proof it was Mr. Reilly, the butcher. John easily agreed. So now, the three of you sat, Sherlock perched in his chair watching and sometimes screaming at some random crap telly, John skimming through news articles he didn't completely understand, and you studying a potential case on your laptop. The peace and serenity of the scene was vanquished by the annoying buzz of John's phone.
"My brothers are in London, I presume?" He gave you a wary glance. It wasn't hard to deduce it, he had earlier accepted a similar phone call, and after that he had been very reluctant to be alone with you, or near you, even. He was afraid to let it slip. He answered the phone.
"Hello?" He asked, and after the voice answered he looked to you, and nodded solemnly. He opened his mouth to apologize, but you soon cut him off.
"It's fine, John. Nothing they can truly do. Go on, answer him." He shot a worried glance towards you.
"221B Baker Street." He answered, extremely reluctant. Yes, they were your brothers, but it felt like he was betraying you, his friend. Of course, it was Sam who had called, but he still hated the idea of seeing Dean, again, as well. The call ended after Sam said his thanks. The case you were studying appeared to be a simple haunting, but your mind kept drifting back to that criminal you met the first day you were in London. He was dark, mysterious, and, given his work, extremely dangerous. You tried to fight off the rising heat in your face every time you thought about him. Those full lips, dark eyes filled with secrecy, how every lock of obsidian hair was perfectly in it's place. Everything about him screamed perfectionist, his Rolex was underneath his cuff, yet aligned perfectly, his hair, his crease-free suit, but on further inspection it was clear it wasn't him who was a perfectionist. He wouldn't let them near his tie, it was slightly crooked, so obviously not a lover. Someone who loved him, probably, but their relationship was strictly professional. Somehow, that pleased you. There was his phone, it was sticking crookedly out of his pocket, and his cuffs were uneven. Business appearance, and he definitely cared about it, but definitely not a perfectionist. Perfectly manicured nails, so definitely high-maintenance. Goons also had the same level of personal grooming, so that much was obvious. What was also obvious, was that meant they usually handled more than just personal security. Gunpowder was evident on their clothes, but cleaned from their hands, so Mr. Criminal doesn't like talking to the common wealth. Those who request his services. So why all the hair gel, manicures, the bloody suit? Expensive, all of it. So why waste money on it? Wasn't because he could, he could've gotten much better stuff, but that would mean he couldn't play it down, either. So, why? Why be at the airport on the first place? Business deal. It could be he was there to meet someone, someone on his side, but then he would've dressed down, tried not to attract attention, but he didn't do that. No, he dressed up. He was there to meet someone, but they weren't on his side, not before the meeting, at least. He was watching for anyone, that says he'd already met with them. Stuck around to let his security team sweep the area. Deal went good, but he didn't trust them. He would've seen you as a threat then, so why didn't he kill you? He knew you had weaponry, you knew he was a criminal, yet you were still alive and well. Interesting. John's phone dinged, pulling you from your thoughts.
"They're on their way. They want to know if you saw the Greenhouse Case?" John was fully aware of what was out there, and he knew how to hide it, even from someone like Sherlock.
"I've seen it, I'm aware, and if they want me to wait, I can, but I think it would be best if I joined them." John nodded, sending your response to the brothers. The change in speech pattern didn't go unnoticed by the great detective, and he stared curiously at you.
"I thought you and your brothers hunted for work?" He accused. Thinking quickly, you smiled, giving a gentle laugh as you did so.
"We do, but Sam has a fascination with dolls. To keep it a 'secret', we call them 'cases' whenever a new one is found." Accepting the, frankly ridiculous, answer, Sherlock went back to his program.
"When am I meeting them?" You diverted your attention, bringing it back to John.
"They said two hours." You nodded, checking the time. That have you time to prep, and hopefully become 100% sure of what this was. Ghost just didn't quite sit right with you...

"I just don't think it's a ghost, guys." You stated your opinion once more, knowing the facts pointed to either ghost or demon. You believed the latter.
"You left, you don't get an opinion!" Dean snapped, causing both you and Sam to roll your eyes. Of course, you had an angel blade and the demon one on you, just in case, but you were done arguing with Dean. All three of you snuck through the house, Dean and Sam believing the corpse to be in the basement. Of course, when thy opened the door, they were jumped by the strong smell of rotten eggs, and you guessed it, a demon.
"Well, well, well. Would you look who it is? The Winchester brothers all the way here in my little town? I'm flattered!" You had hid behind the door, the demon only seeing Sam and Dean. You saw Sam get slammed up against a wall, and guessed Dean was too, despite being unable to see him.
"You know, there's a hunt going on, for your sister. Lucifer's too scared to send anyone, but on the opposite side of the tracks, the Men of Letters want her. Need her, even." The demon taunted, not realizing you were there. Idiot. Kicking the door in, it smashed on the demon, releasing your brothers. Before he could reorient himself, the demon blade was in his abdomen. He fell in a pool of his own blood when you pulled it out.
"Well, let's leave them a clue then."