"You're serious?" Caitlin stares at Joe like he's speaking a different language, one that she's never heard before. He's found her in the Speed Lab, staring at reams of data that made little to no sense, but it still makes more sense to her than the words that have just come out of his mouth.

Joe, on the other hand, doesn't blink. "I am."

"Joe..." Caitlin reaches up to rub the bridge of her nose. "We're trying to stop the end of the world..."

"Again," he interjects calmly and she resists the urge to smile.

Only for a second because once she sees his lips turning up it's impossible not to smile back at him. She's long since thought that Joe West's smile was a superpower all of its own. "Yes," she allows. "Now is not the right time to ask me out."

"I think it's exactly the right time." Joe shrugs and takes a step towards her. Her heart rate speeds up in response. "We're both single again," he reminds her, and for once the reference to Julian doesn't sting. "And Caitlin... I've missed you."

His voice is low, sincerity ringing in every syllable and she looks down, swallows hard. "We tried this once before, remember? It didn't go well."

"That's not what I remember." He steps closer to her now, close enough that she can smell his cologne, feel the heat of his body. It brings back so many memories and she has to marshal all her self control not to lean into him, rest her head on his shoulder the way she used to. "I remember two people who had lost a lot finding something good together. And the only reason we didn't keep on doing that was because we agreed Iris didn't need another reason to be mad at me."

"So what's changed?" She drags her eyes up to meet his, finds them as warm as the hand that's suddenly holding hers.

"Everything," he tells her simply.

She opens her mouth to protest but shuts it again when she realises it's true.

Back then, they'd only just started seeing one another when Francine came back and Iris and Joe's relationship had exploded. She'd been finding her way back from losing Ronnie, since then she'd dated Jay, even if she'd rather forget that particular dalliance, and even if things with Julian hadn't worked out, the memory still made her smile. She'd negotiated a way to deal with her powers, at the same time as he'd made his peace with Iris, had begun dating Cecile, even if that hadnt worked out, hadn't ended as well as her relationship with Julian either.

"Caitlin, we were friends for a long time," he tells her. "Before The Flash, before any of this..." He waves his hand and she remembers all those nighttime talks in STAR Labs as he'd been sitting beside Barry's bedside. "And I miss my friend." His hand tightened around hers. "I miss you being more than my friend. And this whole end of the world thing... well, I'm thinking of things I'd like to change."

There's a lump in her throat and she has to swallow hard. "And I made the list?"

"Sweetheart, you are the list."

It really isn't fair, Caitlin thinks, that with a few words he has the power to reduce her to a trembling mess who has no choice but to step into his body, wrap her arms around his waist and take a deep breath.

And it really isn't fair that doing that has the power to make everything better.

"You're my list too."

The words are out before she can think about them, certainly before she can stop them and his hands land on her shoulders, slide down her back. She feels him press a kiss to the top of her head, hears a smile in his voice when he speaks.

"So... after we stop the end of the world... dinner?"

Once again, she doesn't have to think about her answer. "I'd love to."