"Mac, no! Please, just – hold on."

Will pants silently, his voice breathy as he pleads with Mackenzie, briefly stilling her disjointed and jaunty movements. Swallowing, Will feels his mouth run dry – he hadn't planned this far ahead, he'd just wanted to apologise: to stop her.

"You fired me, Will," she points out coldly, her hands full with folders that she's considering silently – only half-listening to what he's trying to say. Taking in the shambles that is her desk, she sighs wearily and shoves one of the folders into a waiting box – the other is binned mercilessly.

"I – I know. I just, don't do this, Mac. You know I was just mad at the time. I can't – won't – fire you, Mac. Not now." Will's eyes are pleading, his voice trembling with emotion. "Please, Kenzie, for me."

"What's for you, Will?" she snaps, her eyes slits as they narrow in poorly concealed anger and frustration. "Do you want me to stick around to get the shit kicked out of me by you for another two years? Or would you rather watch me get dragged through the mud and put our staff through hell so that you can keep your pride in front of Jerry Dantana? Or is this about humiliating me in another way entirely? What's it going to be, Billy? What's in store for me if I stay?" Mac uses his nickname caustically, practically spitting it at him with rage.

All of Will's previous chagrin dissipates, leaving him feeling hollow and shocked. The fact is: he deserved all of that and more and he can't justify asking her to stay after he's been such a colossal dick. Scrubbing his face with his palm, Will hears Charlie's words ringing in his ears – closely followed by his own revelation: but for the one thing she did wrong, Mac had done everything right. Even if she still wants to leave afterwards, Will decides that she deserves – no needs – to hear that.

"No – I, Mac, listen to me. Please," he pleads, "I want you to stay because you're the best of the best – screw everyone else. I need you here because without you I'd still be covering crap and Don would be with CNN and I'd – fuck it." Will stops, practically growling in frustration. "Mac, I need you here with me because you make me the best I can be – you always have. Except for the one thing you did wrong-"

"I thought you were apologising?" interrupts Mac snarkily. Her expression softens marginally, but her eyes remain icy.

"I am – just y'know, let me finish! I was going to say: except for what you did wrong, you did everything right, Mac. Everything. All these years I held that stupid thing against you instead of recognising all the good you've done – for me and everyone else here. Even if it's not for me, I need you to stay and continue what you started, Kenzie." Will exhales, winding down from his emotional outburst.

Mac looks at her desk, shuffling some papers between her hands as she attempts to formulate a response. Finally, she settles for addressing the most recent and humiliating incident. "And the degradation, Will? The pranks? Will they continue?"

"You're talking about the ring," he acknowledges guiltily, swallowing as he feels the weight of it in his jacket pocket.

"Yes, Billy. The ring," she says pointedly.

It was now or never, he realised.

If he didn't do anything, he'd lose her – maybe forever, this time.

"Well, about that-" he begins.

"Don't tell me – you used it to propose to one of the countless bimbos you screwed. But, when it went south you thought you'd kill two birds with one stone by keeping it?" she interjects bitterly.

Guiltily, Will shifts his weight between his feet, attempting to ignore her interruption as best as he can.

"The ring – I never sold it. I couldn't, Mac. I- I came here to ask you to stay, yes, but also to tell you that, well… I love you, Kenzie. I can't stop myself from loving you any more than I can stop the Earth from orbiting the Sun – it's just a physical law of the universe and you are my Sun. Mac, I – will you marry me?" he blurts, unable to hold himself back any longer.

Sheer and utter shock flit across Mac's face, her eyes narrowing suspiciously.

"Three hours ago you wanted me gone – what changed?"

Sighing at his own stupidity and cursing all of the idiotic things he'd ever done to her, Will raises his eyes sincerely to Mac's. He's met with a harsh gaze – cold but mixed with something that looked an awful lot like longing – and hope.

"I realised that I can't lose you again," he says simply, stepping forwards. Will takes a chance and presses his palm against her cheek, relieved when she doesn't resist. "I realised that I couldn't bear the thought of not spending every day with you, infuriating though you can be," he murmurs.

Chuckling quietly, Mac looks up to meet his eyes, her own glistening slightly as she sniffs quietly. Will lowers his gaze to her lips, suddenly filled with the longing to just-

No. He has to do right by her.

Reaching into his pocket, Will pulls out the turquoise box, hastily extracting the ring from the infernal thing and presenting it to her in earnest, nestled between his thumb and forefinger.

"So…? Will you? Marry me, I mean?"

Mac smiles widely, saying nothing as she reaches for his face, pressing her lips against his ecstatically.

"Does this answer your question?" she asks, repeating the action as she whispers against his lips.

"Uh, not exactly," he murmurs. "Is that a yes?" he asks hopefully, not daring to assume anything.

Huffing with good-natured disbelief, Mac nods, accepting the ring as he slides it perfectly onto her finger before returning his lips to hers.

A physical law of the universe indeed.

Hi guys! I hope you enjoyed this and, if you did, please leave a review :)

This was based on LilacMermaid25's prompt on Tumblr: When Will goes to propose to Mac, she is already packing up her office.

I hope I've done it justice! :)