Whether Team Flash knew about their irregularly regular get-togethers or just suspected it, Barry never mentioned. Snart didn't ask. He was pretty sure they knew something. It couldn't have slipped past them that the infamous master criminal Leonard Snart was sometimes helping out their precious little hero. Should they really be completely in the dark it was either testament to how good Barry had become at lies and deceit, which was highly, highly unlikely. Or it showed how incompetent Ramon, Snow and Wells were when it came to their asset. That was equally highly unlikely.

Being around the meta Sentinel was satisfying, in a sense that Len hadn't experienced this intensely and deeply before. It wasn't a need, it wasn't some instinctual drive either. He wasn't throwing himself at Allen, but he also didn't stop their get-togethers and he didn't push him away. He refused to call them dates, though in his head that word popped up more and more often.

Len would tinker with the cold gun, read a book, watch some inane show, or even go over blueprints in a blatant attempt to get a rise out of a too silent Flash.

It always worked.

He felt proud of himself then, giving the other man a smirk.

Barry would react with an eye-roll, but he was more at ease and Len could actually feel it. The softness, the response to his more laid-back presence, and sometimes he just wanted to touch that softness. It was something he had never experienced with anyone. He didn't do relationships, only partners, business relations, but never anything closer.

Scarlet was closer than anyone had ever gotten and probably would ever get.

What really had all his alarms ringing shrilly was the fact that Leonard Snart had started to open up himself in turn. He had caught himself dropping some lines about his childhood, about his juvie career, about his sister.

"I know about the scars. Lisa's scars," Barry told him quietly, startling the other man. "When Cisco removed that bomb he saw them. She… told him about the reason, why she has them, how it happened…"

Len felt an unaccustomed flush of hot fury, all directed at his so very dead and gone father. He had his own scars, his own marks, some down to his very soul, but seeing Lisa's was always the worst for him. It reminded him of his failure to protect his little sister.

"Let's say we didn't have the perfectly happy, careless childhood," he rasped.

"No, you didn't."

Neither had Barry, but in a very different way. He would never compare one with the other because both their lives had been very, very different.

As someone working for the CCPD, even if he wasn't a cop, Barry knew Snart's file, of course. Inside out. He had never mentioned it, but he didn't have to either.

Nothing more was spoken of it.

The problem was, that moment had cracked the door open. A small crack, but one that was growing.

That was how he found himself talking about his oldest and best friend. About how he had met Mick, how they had become friends and later partners in crime. A lot was said through simple words, sometimes revealing more than Len had ever been comfortable with someone else outside his sister and Mick knowing.

Barry simply listened. Len could see his mind working, sharp and assessing, missing no details.

"He's a Sentinel?" Scarlet finally asked into the quiet that had fallen.

"Was."

There was a mild frown. "I didn't know you could go off-line again."

Len shrugged, one thumb digging into the soft flesh of the palm of his other hand.

"It's possible."

He didn't look at Barry, only at his fingers, his hands. Reminders of why that had happened were never welcome. Even after almost a decade, he still remembered those horrible months in too much detail. He didn't do guilt and blame, but when it came to Mick, he felt all of that. It had been a job, his plan, and it had gone sideways so fast, he had had whiplash from it.

"The fire," Barry mumbled.

Trauma could trigger a Sentinel. Trauma could off-line him. "Yes," he ground out.

"He fled from the ambulance." Len glanced at him and Barry shrugged. "Joe gave me his file to read. I did some digging, since the two of you were making my life hard."

Snart's lips twisted into a humorless smile. "Mick always was a horrible patient."

And resilient, stubborn, strong. Without the resilience he would most likely have lost use of his arms or the whole limb. It was testament to the peak physical condition of a Sentinel that he hadn't.

"His Sentinel went catatonic."

It wasn't even a question. Still, Len found himself nodding. "He switched himself off."

And why was he still handing out information? Why had he even started talking about it? Why did he talk about his friend, revealing personal information, opening himself up for the old pain to rise again?

Because it was Barry. Because he felt comfortable around the younger man. Because the pull never stopped, was always there in the background, and he wanted it. He wanted a lot.

He, Leonard Snart, a loner. He wanted and he wanted more every time. He gave pieces of himself, offering little glimpses into who he was, even though Barry had to know his file. The erased file, sure, but he had read it. And Mick's. He was giving this meta Sentinel more than he had ever given another person.

"He zones on fire?" Barry asked calmly.

"Zoned. Past." He gave him a dark, dark smirk. "Mick was sight and touch, with a little bit of scent."

He had lost sensation in parts of his burned and scarred skin. His hands hadn't been affected, but both arms and parts of his shoulders. There were patches on his back where touch couldn't be felt.

But he had still been a very efficient bounty hunter in the shape and brainwashed form of Chronos. The Sentinel, even when gone dormant sense-wise, had still been there. It was in Mick's blood. Others had called him a brawler, the battering ram, the muscle. Len knew there was a sharp mind hidden behind that thick skull. Seeing Mick deteriorate so badly, become unstable and obsessive with fire after the accident, had left its own scars with Len.

"Sorry," Barry said softly.

"Not your fault."

Fire had triggered him into coming online. Fire had locked his abilities once again, pushing the other man into darkness. He had become unpredictable, volatile, a loose cannon. Len had had a modicum of success controlling his partner, giving him the illusion of stability. It hadn't been perfect and Mick had done some really stupid and close to horrendously terrible stuff, but he had survived.

"You weren't his Guide."

He blew out a little laugh. "No, Scarlet. I wasn't and never could have been. No potential, no ping on any scale, remember? I was just a friend and partner."

Barry nodded slowly.

Nothing more was spoken about it, but it was back on Len's mind. He wondered how his oldest friend was faring aboard the Waverider, if he was still with them, if he had just up and left, if he followed a path Len had seen him take even before that fateful day at the Oculus station.

The next time Barry dropped by with a cake box that contained more calories in colorful pie and cake variations than all the food in Len's fridge added together.

"Iris made me do it," he muttered as Snart eyed the assorted slices.

"Your sister made you buy pie?"

He shrugged. "I didn't buy it. It's leftovers."

"You bring me leftovers. Scarlet, I'm touched." Snart snagged the chocolate slice for himself.

"It was that or throw it all away," Barry replied playfully.

"Like it would go to waste on your massive appetite, Flash," he drawled and settled on his work stool. "If I ever need food to be eaten, I'd call you."

"If that's the thanks I get for bringing cake…" he griped.

Len smirked. "That's not even close to the food you owe me, Barry," he teased. "But my compliments to your sister. It's delicious."

Barry devoured the rest, looking at ease and content.

Throughout the 'eat the leftovers' visit was the first time he heard about Allen senior, about Henry getting out of jail a free man, all charges dropped. He heard about Barry's father staying for a few weeks, then packing up a van and just driving off into the sunset.

Len couldn't say he knew what a real father-son relationship was like. His own had been the worst and good riddance to him. But Barry had held on to the belief that his father hadn't killed his mother; he had stood by him, the conviction never wavering.

Now his father had left him again.

He watched as Barry fiddled with the remote, looking lost.

Len said nothing. There was nothing to say, nothing he could say.

Still, despite the emotionally difficult topic, when he left, Scarlet seemed a lot more at ease. Calmer. Relaxed and centered. Green eyes met blue and the younger man smiled softly.

"Thanks for listening."

"Nothing much else to do. TV was boring and the radio's busted."

The smile widened, those expressive eyes filled with emotions Len refused to label. There was a long moment between them, the pull so intense it almost physically tried to draw the other man in. He felt the thrum of the Speed Force, saw it manifest like ethereal, surreal wings without much of a consistent shape.

Barry didn't speed off right away. Not really. He walked a few paces, then there was only dust.

Len just turned back to his tablet, eyes distant. For the very first time in his adult life, Leonard Snart wondered if things between them could be more, could be different, would have been different if he had been born with the potential to be a Guide. Because the first time in all those years, he thought being a Guide wouldn't be the shackle if the Sentinel he bonded to could be Barry Allen.

They were by now extremely comfortable with each other, in battles and in their more private moments. Cold was now so accustomed to fighting alongside The Flash, he easily picked up small things, nuances, a change in the speedster's body language, his tone of voice. He reacted accordingly, their communication close to non-verbal. He almost felt the other man's intentions and his own instinct had him adapt.

His mind, used to planning ahead in detail and strategizing to the second, adapted in turn. He found he was quickly forming new plans, rendering a scene, taking in the pros and cons of each tactical move, and he discovered that The Flash was starting to listen to his plans, to adapt in turn. The hot-headed approach was suddenly more controlled.

It was then, months into their little arrangement that had by now become part of his life, part of him, that Len noticed Barry using his senses. He couldn't magically feel it, but there was a change to The Flash's approach to some situation, a moment of complete stillness that lasted a fraction of a second and was still so much longer to someone so in tune with time.

"You used your sight," Len remarked casually, but with a very knowing grin and not just a little bit of pride.

Barry raised both eyebrows. "Did I?"

And wasn't that teasing and playful? Len thought, refusing to analyze the emotions the smile set free; that the tone of voice set free.

"When your little Lightbringer flared."

The woman had been a meta and could produce intense flares of light. She had already blinded a guard and burned Barry's retinas the first time. It had taken him almost ten hours to get his sight back. Len had only heard about it afterwards, which had had him want to hurt something or someone. He really needed to get a hold of his protective instincts.

"You switched off your sight and found her through scent, hearing and touch. Good work. I didn't know three senses could be piggy-backed."

Barry shrugged. "I've been testing myself. I've tried some stuff. It worked."

Len chuckled and there was a moment of pride shooting through him. "And it only took you how many years?"

"Shut up." There was no heat behind the words.

"Does your team know you're letting the Sentinel come out to play?" he teased.

Barry scrubbed a hand over his neck. "Yeah. Caitlin wants to run tests. Wells is cautioning me not to overdo it. Cisco is looking into how to change the suit's gloves to make them more Sentinel-friendly when I use touch. I told him it's fine. Not sure he won't tinker around."

"How is touch within the suit?" Len asked curiously.

"Actually, not too bad. I mean, I'm not one hundred percent receptive because of the tri-polymer, but I can sense a lot when I dial up. And no adverse effects from the clothing either." The last was added with a smirk.

"The loop," Snart murmured.

It sounded like the perfect Sentinel, but as Barry had said before, there was no perfection.

"How do you train and test your senses?" he asked.

"Want to find a weak spot?"

He tilted his head, lips pulling into a predatory smile. "Actually, yes, I do."

The younger man frowned. "I'm not going to give you an advantage."

"Do you really think I'm that shallow, Scarlet?" he asked playfully. "We have a business arrangement. A deal. I'm sticking to it."

"Then why the question?"

He shrugged. "Curiosity. And maybe to evaluate your approach. Seeing as to how you handled everything so far, it's valid."

Another grimace. "I'm fine, Snart."

"Len," he reproached him softly. "And no, you are not. Hence you coming here. I'm offering a neutral point of view, outside a fight situation. Maybe give you a few pointers, have you run different scenarios from a new angle."

Barry met his eyes, unreadable to a degree, clearly mulling over the words. "How?" he finally asked.

Len grinned. "I'll draw up a plan."

It was how 'just hanging out' turned into 'training a meta Sentinel's five senses'.

Len had no idea if Barry had thought he could keep their involvement in the field of crime fighting a secret. There was a radio in that suit and they could hear him talking, so when he dropped Snart's name, they would come to their own conclusions. Not to mention that Barry ditched hanging around S.T.A.R. Labs sometimes.

There was a reluctant acceptance that Cold was on the scene and keeping Central City's hero from becoming a stain on the ground sometimes. He never talked to any of them directly, never sauntered into the cortex, and he kept a close eye out for any surveillance on him.

"I'm surprised they haven't hunted me down yet," Snart commented. "Tainting their perfect little hero. All fluffy unicorns and caramel-hearted goodness."

Barry looked close to offended.

They had been training Barry's senses while he was using the Speed Force a lot lately. It had become sort of a scheduled regimen. Snart's detailed and very thought-out plans had been adjusted a few times and he was surprised how quickly the Sentinel adjusted in turn, how much Barry was progressing, and how well the meta side and the born Sentinel were in tune.

What intensified after such sessions was the decompression time. The Speed Force felt hyped-up, stronger, whirling all around him, and it settled when they both did. A plug was pulled, the tension disappeared.

It should freak him out, Len mused. It didn't.

And a tiny but growing part wanted him to touch Barry, to just squeeze a shoulder or pat his back. It itched him to do it and he forcefully locked that need away.

Come to think of it, aside from dragging The Flash's bleeding form back to his safehouse months ago and that one moment where he had checked the bullet wound, Len hadn't so much as brushed past him again. Not even to help him up; they kept their distance, both of them. The closeness was there, how near they were to the other all the time, but they never touched.

Now Len just smirked. "What did you tell them? That your loopy meta Sentinel has found his special Guide?"

"You're not a Guide," Scarlet recited automatically, but there was a spark of laughter in those expressive eyes. "And I'm not loopy!"

"You learned well, Grasshopper." He playfully tossed a donut hole at him. "And you are."

"You only had to repeat it about a million times. And I'm not. I'm in a loop. Big difference."

"You are slow sometimes. For a loopy speedster. So what did you tell them?" he asked with a grin.

Barry rolled his eyes at the continued teasing. "That we've come to an understanding. That we have a deal. That maybe you are walking more of a gray line nowadays."

His brows climbed up. "You make it sound like I'm suddenly into non-profit work."

"It's an alliance."

"Ah. That makes it so much better. Still not getting my money's worth out of it. It's also ruining my reputation."

"But you get something out of it or you wouldn't still be around." Barry gave him that knowing smile that had Snart's masks almost crack.

"Enough blackmail material to have you in my pocket, Scarlet," he taunted.

The smile stayed. "Don't tell me it doesn't feel good to help people."

"Sorry, I'm not interested in being a hero."

"You've made a really lousy villain lately," Barry replied.

He met the clear, open gaze, found nothing but warmth and honesty in those eyes. There was something else there, something he didn't dare give a name. Something intensely personal.

"You really are one in a million," Snart sighed, putting enough disgust into it to hide the fondness.

"That makes you one, too, Len," he shot back.

"So they're not going to shoot me on sight?"

"Wouldn't be so sure of that. Cisco's still a little peeved that you have his cold gun and gave the heat gun to Rory."

"Tell him to suck it up and get over it."

Barry picked up the controller that sat on the low couch table and leaned back in the armchair. He raised an eyebrow.

"Really?" Len teased.

"Loser pays the tab."

"That's coming out of your paycheck, kid!" he replied, accepting the challenge.

Leonard Snart didn't get to officially meet the team for quite some time; at least in person. Len had no reason to want to meet them anyway. He knew they didn't trust him and had perfectly good reasons not to. For one, he and Mick had kidnapped Dr. Caitlin Snow to use as bait to trap The Flash. Mick hadn't been at his best back then, a little unstable, a little too hotheaded. And then there was the little fact that Captain Cold had pressured Cisco Ramon into revealing the identity of The Flash to him.

Yes, one could see where this might be a bit of a troublesome meeting should it ever happen.

And why would he seek out the team anyway? He had no interest in walking into S.T.A.R. Labs for any reason. There might be valuable pieces to steal, but not without getting the lay of the labs first, knowing every entrance, every exit, ever nook and cranny. Len would scope the place, the surveillance and security measures, and he would want a possible buyer first.

So when he did meet one of Barry's friends, it was because of The Flash. It would have been surprising if it hadn't been about and because of Barry, but Leonard Snart would never have expected to be tracked down and almost begged to help.