"That's not fair. You live with him, you're already spending more time together by default. He gets to sleep at my house every weekend, and that's final."

"Absolutely not. What if a case comes up? It will take him longer to meet me there, we'll be wasting valuable time!"

"Do I even get a say in this?" asked John, exasperated.

"No!" exclaimed Mary and Sherlock at the same time, turning to look at him with an annoyed glare.

"And it's not unfair," continued Sherlock, looking once more at Mary. "It's hardly my fault John happens to live here. That's outside of the arrangement. Besides, I already compromised accepting not to interrupt your dates unless a case comes up. What more could you possibly want?"

"But that's the whole point of this! If we are going to share him, then we both need to be with him the same amount of time. I'm not even going to mention the fact that I'm his girlfriend, and should have the right to see him longer than you do. So stop arguing with me Sherlock Holmes, and accept the deal."

Sherlock deflated a bit. Yes, you are his girlfriend. And you'll end up taking him away altogether, so why can't you let me have him now? "Fine. But if one of those nights overlaps with the end of a case, he stays here. We have a ritual of ordering Chinese take-away after one, and I'm not letting him be absent from those."

"Fair enough. Deal," she said, holding out her hand.

"Deal." He took it in a firm grasp, shaking it once; but released it immediately.

"Good." Mary smiled slightly at him, calmer now that they have finally reached an understanding. "I should be going then, it's late. I'll call you tomorrow, John."

"Oh, remembered I'm here, haven't you?" He grinned and accepted the chaste kiss on his lips. "I'll call you tomorrow, all right?"

"Sure. Bye, Sherlock." She kissed his cheek, amused at the detective's irritated glare, and left.

As soon as she closed the door, Sherlock collapsed on the couch, sulking.

John sat beside him and raised his arm so the detective could snuggle up to him. Sherlock's face rested on the crook of John's neck, with and arm curled around his stomach, while John petted his hair.

"Sherlock, I know you don't like Mary." The detective tensed, obviously uncomfortable with the subject, but John kissed his head in order to calm him down. "I know you don't like her, and it's fine. I mean, of course I would like it if you two could get along. You're the most important persons in my life. But hear me out." He tilted Sherlock's head up and locked eyes with him. "What I have with Mary doesn't change anything. We're still us, and no one is going to change that."

"But things will change eventually, John. She'll demand more of your time; you'll start spending more and more nights at her house, not just the weekends, and one day you'll want to marry her, and have kids, and... What about when she starts to suspect that something strange is going on? We're hardly the normal definition of friends. She'll get mad and tell you to stop this, and in the end- In the end, it'll be just me again." I'll lose you. I can't be without you. Please don't leave John, you can't leave, everyone always does, please stay, please don't...

"She already knows, Sherlock."

The detective lost his train of thought and looked at John, confused. "What? She knows? When-?"

"Almost from the start, actually. I didn't even have to tell her, she figured it out on her own before I got the chance," said John with a smile. "Told you she was smart."

"But... she knows. Isn't she mad? Or upset? It doesn't make sense."

John thought about it for a moment. "When she told me she knew about us, she said it was obvious. That the moment she saw us together she could tell that, no matter how many woman I dated, you were always going to come first. Because we were soul mates, or something. And I think she was right, you know? I mean, I love Mary, I really do. But Sherlock, this thing we have... I don't know what it is, but I don't want to lose it. I wouldn't give it up for the world. And she understands that, she is okay with it." He paused for a moment and grinned. "As long as you learn to share, of course. She does like you most of the time, surprisingly, and she's willing to compromise."

Sherlock just look at him, trying to process everything. He caressed John's cheekbone, as if he were trying to prove himself that yes, this is real, John's right here and he won't go anywhere. "John," he breathed. "This isn't normal."

John softly kissed his forehead. "Normal is boring anyways."

Author's notes:

This was inspired by House's episode "No more Mr. Nice Guy".While I'm not a JohnxMary shipper, i thought it would be interesting to explore something like this.

I hope you liked it and please, let me know if you see any mistakes :)

Lots of love Xx