*Note: Slight change to ASiB in regards Adlock. I just happen to covet Adlock.
Irene changes everything.
He remembers the incredibly specific directions he gave her regarding Sherlock. ('Don't touch him. He's mine. Play with him all you want, but. He. Is. Mine.')
She ignores him.
She strings Sherlock hopelessly along until he has no choice but to fall into bed with her.
John watches the whole thing on his laptop from his comfortable chair in the living room via the security camera he's secretly installed in Sherlock's room.
The whole affair is not nearly as sexy as John initially imagined, but he can't be too picky.
Irene - in true dominatrix fashion - takes the lead and guides Sherlock to the bed. Sherlock follows like a puppy, and John knows that he will probably follow her every command.
She ties Sherlock's arms together at he top of the bed with his famous blue scarf and strips him down to absolutely nothing.
Irene does absolutely nothing to John. Truly, he's never been very interested in women that way. On the other hand, the sight of Sherlock, helpless, stark naked, and tied to a bed is nearly enough to send John sprinting towards the bedroom.
Irene starts off slow. She treats Sherlock like a beginner, and frankly, John can think of so many more, creative things that he would do that man (if he could).
Irene teases Sherlock. She grabs him hard and brings him to the brink and stops right before he's about to come.
Worst of all, Sherlock begs (more than twice).
John hears the whimpers and the cries and the thuds and tries to imagine that he's in there instead of Irene.
Finally, she takes them both over the edge. Sherlock comes and Irene collapses on top of him and John can't help but feels a pang of jealously knowing he can't make Sherlock feel like that (yet. He's determined to make Sherlock work for it - really work for it - first.)
John takes it upon himself to remind Irene that he is the only one who can make Sherlock beg. He has her beheaded in Karachi and that's the end of that.
Except Sherlock saves her.
John's devotion to the detective falters for a moment.
(His devotion is only revived when sees Irene's body laid out before him, covered in needle marks, cuts, and finally, a fatal bullet hole to the back of the head.)
Sherlock is John's again. They sit closer together than they used to, exchange more frequent touches, spend more time together. But there's a hollowness in Sherlock hat wasn't there before; there's something missing in him.
John vows to make Sherlock whole again by any means necessary. Even if it means shattering the world around them to find the perfect piece to fit the detective.