"You know they won't let you on crime scenes any more if you carry on behaving like that"
"John, they've let me on crime scenes for years and I've always behaved like that, why would that change?"
"Because people get fed up Sherlock"
"Oh?" Sherlock said, turning to look at John. His face was dimly lit, the only light coming from the streetlamps they passed in the cab, but John could still see he had one eyebrow raised.
"What about you, John?" Sherlock continued. "Will you get fed up, move out, leave me all alone? Oh but then where would the great, all knowing John Watson go? Clearly he needs someone normal, not messy, nine to five job and all that for his stupid little mind. Maybe you'll find an idiotic girlfriend, you always go for the idiotic ones John, maybe they make you feel more intelligent, move in with her. Make her food, clean up after her, all the little things you think make you useful. There wouldn't be much excitement of course, not like we have, unless you count sticking your head in between her-"
"Enough." Though John spoke quietly, his tone was enough to stop Sherlock. The cab was quiet, save for the quiet sound of the radio, and the occasional car speeding past. John could feel Sherlock's eyes on him, but he determinedly stared straight ahead.
"I'm glad to know that's what you think of me, Sherlock, thank you."
"I didn't-" Sherlock tried to interrupt.
"No, I'm talking now. I know I'm not as clever or brilliant as you. I've always been boring old John Watson. I've heard it from a lot of people, Harry, my parents, friends, girlfriends, but I never thought I'd hear it from you.
"I didn't say you were bor-"
"Yes, but you implied it. You know, after all I've done for you, I thought maybe you actually appreciated me. I cook for you, I clean up after you, I make sure you don't get yourself fucking killed. I don't really enjoy those kinds of things, cooking and cleaning. I do them though. Do you know why? I do them because I care about you. It also makes me feel useful, I suppose, like someone actually wants me, needs me around, and generally gives a shit about me."
"John, I don't…" Sherlock looked lost
"I put up with a lot from you Sherlock, because behind the mess and experiments and insults is a genuinely nice man whose company I enjoy. So I don't appreciate you acting like I would just walk out without a backwards glance. Maybe you could move out and leave the great, all knowing John Watson behind, but I'm sure as hell not leaving."
There was a long silence after John finished. He could still feel Sherlock's eyes boring into him. He wouldn't look at him, couldn't look at him. Instead, he stared out of the cab window, counting cars and trying to put himself in control of his emotions. While he always knew Sherlock considered him to be considerably less smart, it hurt John to physically hear him say the words and mean them. Yes Sherlock called him stupid all the time, but never with such malice in his voice. He had thought Sherlock appreciated his attempts to look after the mad man, but apparently not.
Then he felt a light touch against his hand. John stopped breathing, as if the slightest movement might scare Sherlock away. Very slowly, Sherlock entwined his little finger with John's, and John could feel his hand shaking. John let out a long breath, and gripped Sherlock's finger back.
"I know that I said some…things, that may have upset you, but…I do not believe them to be true. I said them to make you hurt, even if they were lies. I was perhaps a bit worried that you were thinking of leaving and that distressed me a small amount, so I lashed out at you in an attempt to hide my own feelings. I apologise, John. I find you neither boring nor stupid, and you are a very important part of my work, so thank you."
This was Sherlock's equivalent of begging on the floor for forgiveness, and John knew he wouldn't be able to remain angry after his confession. He was always worried Sherlock was going to finally decide John was a more of an inconvenience than a convenience and ask him to leave, but it seemed Sherlock was also afraid of being left alone again.
"Thank you Sherlock, that means a lot to me. And why would you think I wanted to leave you?"
"Because everyone does eventually, they all leave me. They say they'll stay but they get fed up eventually." He said this quietly, staring at his knees.
John felt his heart break a little at these words. All his life Sherlock had been left alone by people who claimed to care for him, and was now waiting for John to do the same. Yes the man was difficult to handle, but once you got past the mad exterior, you found a wonderful interior.
"You daft bugger. I'm not leaving you, okay? You're the best thing that's happened to me in a long time. If it wasn't for you I'd probably be in that bedsit with my brains blown out all over the wall." John laughed weakly as the finished his sentence, but soon quietened at the look on Sherlock's face.
"You must never talk about killing yourself again. I will not allow it. You are not allowed to end your own life. Nobody else is allowed to end your life, I can't even begin to-"
Sherlock looked on the verge of hysterics by this point. His face was a mixture of anger, fear and sadness. John decided to stop him rambling.
"Okay, I'm sorry, I'm sorry." John gripped Sherlock's finger with his own more tightly. "I promise not to kill myself, I don't feel that way anymore, and I'll try not to let anybody else. Besides, you'll protect me, eh Sherlock?"
"Always, John."
Silence fell after this, and tension crackled through the cab. John could see the cabbie sneaking glances at them through the rear view mirror, but he couldn't bring himself to care. All that was going through his mind was Sherlock Sherlock Sherlock. He opened his mouth several times to speak, but no words came out. He felt like something had changed between them, but he couldn't figure out what, why his insides had gone all warm and wriggly. He saw Sherlock open his mouth to speak and his heart started pounding.
"John, I-"
"Here you are boys, 221B Baker Street" The cabbie spoke over Sherlock. John released Sherlock finger to rummage for his wallet, but Sherlock got there first.
"I'll get it John, you go ahead."
John could tell Sherlock was still trying to apologise, so let him get on with paying.
"I'll put the kettle on then." He patted Sherlock's hand, and then exited the cab. He was sure whatever Sherlock wanted to say could wait for another time.