A/N: I had a lot of fun writing this one. Zack/Brennan is so cute, even if it isn't really romantic. :) I hope you guys enjoy!

Though she doesn't know it, every once in awhile he stays as late as she does, just to make sure she's alright. He knows that's it's really Booth's job he's doing, but sometimes Booth isn't there, and those are the evenings he stays until she leaves and then purposefully takes the bus by her apartment to make sure she got back safely.

When he thinks about it, it sounds sort of creepy, but it really isn't. Ever since… ever since they almost lost her, he's begun to see that she's actually the glue holding them all together. She keeps Angela from being too crazy and she means the world to Booth. Before, she was the only one who didn't know about Hodgins' wealth, and even now the two share something special.

Almost dying does that to people.

And him? Well, she's the only one who's ever really understood him. She's been where he is, and he's grateful that she knows he's not just a cold, intellectual shell, but an actual human being who has feelings that he's just not quite sure how to convey.

This case… This case is a tough one. It's taken its toll on all of them, but especially her. He can tell by that look she gets in her eyes, the one that means that she just can't distance herself.

That's happened to him, too. He remembers when she told him to put his heart in a box, and whenever she starts to look at a skeleton like that, he offers up that piece of advice. He's pretty sure it helps, because the look recedes a little and she gives him a small smile, but he can't be positive because he knows he's not good at reading people.

But during this case, that doesn't seem to help as much as usual. She's staying later and later, and he's getting worried. One evening he passes her office quietly, and for the first time he sees her sitting at her desk, in the dark, computer off, doing absolutely nothing. She's never stayed late and done nothing before, and it drives him to pass by her office another thirteen times before gathering up the courage to knock softly and open the door.

And when the crack of light he lets in falls across her face, he sees that she's crying.

That worries him even more, and he finds his hand is trembling a little with nervousness as he enters the room and shuts the door behind him, because he doesn't have much experience with comforting people.

"Dr. Brennan?" his voice is quieter than ever, but she finally looks at him, using her right hand to wipe the tears from her cheeks. Her smile holds a hint of embarrassment, and he can see that he's not the only one feeling a little awkward, and that somehow relaxes him little bit.

"What are you doing here, Zack?" she inquires, and he's immediately nervous again because he knows he can't tell a lie to save his life.

"I was worried about you." He's slightly proud that his voice is a little stronger now.

She nods slowly. "Tough case." It's only two words, but he understands that if she elaborates any further she might break.

"You couldn't… you couldn't put your heart in a box." It's the only thing he can think to say, and he hopes to the God he doesn't believe in that it was the right thing.

Putting her hand to her forehead for a moment, she laughs slightly, and he panics a little.

"I'm sorry, I didn't mean-"

"It's alright, Zack. You're right. I couldn't."

His sigh is full of relief, and after a moment of hesitation, he pats her on the right shoulder with an open hand. It's sort of become their method of communication when words won't suffice. She reaches across with her left hand, placing it atop his as it comes to rest on her blouse.

Her thumb brushes the side of his hand, and for a simple, split second he forgets that she unofficially belongs to Agent Booth and takes a moment to imagine how things would be if she belonged to him. But it passes quickly, and before he realizes what's happening, she's pulling her jacket from the back of her desk chair as she wipes her eyes one final time.

"Do you need a ride home?" she asks, and he's torn between accepting her offer and just taking the bus for some time to think. But he figures she needs company, and he nods.

"Yes. I do."

"Let's go, then." She gestures for him to exit first, and she locks her office door behind them. As they make their way down the darkened, deserted halls of the lab, she unexpectedly stops him, wrapping him in an impromptu embrace.

For once, he stops analyzing and puts his arms around her, too.

"Thank you, Zack." She whispers quietly, and he's glad that for once, it seems like he's managed to do the right thing.

When she pulls away, he's nearly floored by the kiss she presses every so softly against his cheek. She keeps walking, and he takes a moment to regain his composure before rushing off to catch up with her.

He hopes the ride home will be dark enough to hide his face, because he's pretty sure he won't be able to stop blushing for awhile.

End