No spoilers or timeline, just the ramblings of a serial procrastinator trying to avoid a Shakespeare essay at 3am. Enjoy.
In all honesty, she has in the past given considerable thought to the where's, when's and why's of what anyone who knows them would classify as inevitable.
From dramatic confessions at hospital bedsides, or re-enactments of Somalia, in which she is less damaged and he is more daring, to wild and spontaneous acts of tension relief in bathrooms or elevators.
It's been building up for a while.
Working with him is often an exercise in self control. It takes self control to remember that the bullpen is in the middle of a room full of people, or that crime scenes often have Gibbs lurking nearby.
He tests her, and it infuriates her to know that sometimes he doesn't know he's doing it. It annoys her even more when he does know. She will often teeter between the desires to pummel or screw that smirk off his face.
He will lean over her shoulder to look at evidence on her screen, feeling his warm breath on her neck makes her think of feeling his warm breath in other places. He uses her thigh to steady himself as Gibbs takes a corner on two wheels, his hand wasn't even that high.
On the really bad days, it can be as simple as him catching her eye across their desks.
It is a timer on a bomb, inexorably winding down to that moment when she will snap. On second thought, it is not a timer, timers are predictable. You know when the explosion will occur. Ziva has no idea how much longer she's going to last. No, this is a hand grenade, with the pin pulled. One wrong movement and her efforts will crumble.
She's looking forward to that moment.
In the end it was not her will that broke first. And that surprised her, she'd been so wrapped up in her own efforts that it hadn't occurred to her that he'd been struggling just as hard.
She remembers the way he would pay scant attention on movie nights if she succumbed to the heat and wore shorts. Or the way he'd sniff at her hair when he leant over her shoulder, the sniffing would usually be followed by a moment's silence, as if he was composing himself.
The look in his eyes when they met hers across the desks.
Nor is the moment particularly epic. At least, it would not seem epic to someone else.
She was at his door, complaining about the rain and the fact that she wasn't going to reach her car without getting soaked.
He appeared next to her and offered her a hoodie, it was ridiculously big on her but she liked the way it immersed her in his scent.
He had this weird look on her face, she didn't take the time to decipher it, instead she just thanked him and kissed his cheek.
He cupped her cheek in one hand, and it was a mark of her rapidly failing self control that he didn't really need to try to pull her face back up. He was tentative at first, but when she responded, the intensity heightened.
She was vaguely aware of him pushing his door closed again.
Turns out, the secret to his self control was her wearing his clothes.