A/N: I just. Loved the Killer Frost content tonight. And I need her to team up with Barry more. So I wrote a quick thing


Nora ran, round and round the speed lab, lighting up the walls in purple and yellow flashes. In that moment, those sparks of color were the most beautiful things Barry had ever seen. His daughter was alive and happy and running, everything she hadn't been yesterday. Yesterday, the most terrifying day of Barry's life.

His hand twinged and he flexed it, glancing down at it, remembering the lightning that had surged around it, more powerful than any lightning he'd ever thrown before. Ready to kill in cold blood. Ignoring the cries of his wife to stop.

"What are you moping about?"

Barry turned at the sound of Killer Frost's voice. The echo around it, like an icy breeze sliding by, had once instilled terror, but now he smiled. "Who says I'm moping?"

She was pushing in one of their dry-erase boards, a large bow dangling from one hand. She waved it vaguely at him. "You're not smiling."

"I have to smile to be happy?"

Frost rolled her eyes. "You're always smiling. All of you are. Working here is like working with puppies."

Barry chuckled, leaning back against the railing. "What's the board for?"

"I may have… destroyed all of Caity's research into the cure."

Barry arched an eyebrow. "That seems extreme."

She sighed, picking up a marker to start writing. "I was trying to make a point. Ralph managed to talk me out of it."

"Ralph, huh? And you're apologizing. Wow, you two are getting nicer," Barry teased.

Frost cast a glare at him. "I'm not apologizing, I'm fixing what I broke."

"Whatever you say, Softy Frosty."

She crossed her arms. "If you're going to analyze me, then I get to analyze you. What are you moping about?"

Barry snapped his jaw shut.

"Hmph. That's what I thought. Always ready to talk about everybody's feelings but your own."

She turned back to the board, writing down equations.

It was Barry's turn to sigh, scrubbing a hand over his eyes. "I just… I was ready to kill him. Cicada. I've killed a couple times, out of necessity, but never… never like that. Never premeditated."

"And it scared you," Frost finished.

Barry nodded.

She shrugged. "You wouldn't have done it."

"I was going to."

"You wouldn't have."

She spoke with such confident, dismissive ease, and it frustrated Barry. "I would have, Frost. I was going to. I was ready."

Frost capped the marker, turning to him. "No, you wouldn't have," she repeated calmly. "I don't care how angry you get, Allen – you won't kill in cold blood."

"How do you know that?" Barry challenged.

Frost held up her hand, letting icy mist billow around it. "Because I'm the expert in killing in cold blood, Allen. Or, more accurately, I should be. But I'm not. Because of Caity."

Barry furrowed his brows. "What does this have to do with me?"

"My name is Killer Frost. But even at the start, Caity was always in the back of my mind, begging me not to kill. Against my better judgement, I listened. She became the moral compass I wasn't supposed to have. It might be a struggle sometimes, but as you know, I end up listening to her. I would do anything to protect her, but I always manage to stop short of murder.

"But you, Barry Allen, don't have that problem. Under normal circumstances, you would never dream of killing, and you've been that way your whole life. The only person I've ever met who might have a more annoyingly pure heart than you is your daughter. And on the rare occasions your moral compass falters, you have a whole family of Caitys, talking you out of it.

"Even when you're pissed as hell, you would never kill in cold blood. Because you can't. If your heart doesn't tell you no, then your heart will listen to someone who is saying it. Just like you listened to Nora."

Barry looked at her, searching her eyes for any hint of dishonesty. But there was only certainty. "You really think that?" he murmured.

She nodded. "And Caity agrees."

Barry smiled softly. "Well, I guess if Killer Frost says I'm not a killer, then it must be true."

"Damn straight. Now, is therapy over? Cause I gotta get back to writing equations."

Barry pushed off the railing, heading for the door. "Yeah, Frost, I'm good. Thanks."

"Oh, and Allen?"

He paused, looking back at her. "Yeah?"

She glared at him, emphasizing the words by pointing an icicle-tipped finger at him. "If you ever call me Softy Frosty, or so much as breathe a syllable of that name to anyone else, ever again, I will kill you."

He let a mischievous grin spread across his face. "I wouldn't dream of it, Frosty."

She took a step forward, her glare sharpening. "I mean it."

"Nora! Time to go!" Barry yelled, racing from the room.