Len made it a game to see if Barry tracked the gun or had another way to get a read on him. Snart went about testing all the options as if he was planning a job: make a plan, execute the plan. First was the cold gun. He left it safely stored in a safehouse, but Barry found him. He took it with him, removing the freon core. The result was the same. He actually took the whole thing apart and placed parts in different locations, but the speedster only went to where Leonard Snart was.

So it wasn't the gun.

Next came a thorough investigation into electronic trackers that might be on him or any kind of nifty tech that the lab had developed. He went as far as hiring a hacker to check on tracing software on his smartphone or any kind of other spy software. There was nothing.

And it wasn't just Scarlet alone. While Barry unerringly found him wherever Len was, Snart himself had developed a sixth sense as to where to find the other man as well. Len wasn't a Sentinel and he had no precognitive abilities. There was simple this… knowledge.

He decided to train that new sense, see how far it went, how close he had to be to Barry to get a ping. It was also a new level of thrill to hang around crime scenes, keeping in the background without obviously hiding or looking suspicious. He stayed in surveillance blind spots, watched Barry work, talk to the detectives at the scene, then pack up and head back to the lab.

Len was secretly amused to see this other side of Barry Allen. He was confident in his field of expertise, precise, knowledgeable and very focused on those tasks. The patrol officers and some detectives seemed to dismiss the crime scene techs, going as far as ignoring them, and only some asked questions as to what could already be told about what had happened. When it was Detective West or Detective Thawne, the familiarity and friendship resulted in a different kind of interaction.

Sometimes the Sentinel suddenly stopped and seemed to scan the area, and more than once Len knew Scarlet had discovered him. He never lingered too long on where Snart was, only let him know he had found him. It was a game of Where's Waldo?, Snart mused with a grin. Only he didn't dress up for the occasion.

So he took it to the next level. He wanted to know what Barry was tracking. He changed his scent, using different shampoos and body washes, and alternated between new deodorants. He also had a new outfit for each scene, added a wig once, and a fake beard the next time.

It was fun. A lot of fun. A challenge he hadn't had in a long time, aside from planning a difficult break or a near-impossible heist.

Barry was mercilessly teasing him about it the next time he dropped by for an hour, looking carefree and so very much at ease.

"I can track you by scent, sight, and sound. You really challenged me with the scent part."

"Good." Snart felt pleased.

Part of him wondered about the sense of hearing tracking him. What was unique about a person for a Sentinel to recognize again? He would have to look into it. Since Mick had been all about sight and touch, never sound, Len had never given that sense much attention.

When he found out that Sentinels with trained hearing could locate specific persons they were acquainted with by their heartbeat and pulse, something inside him churned, then curled up. He was unsure what to think of that. Part of him was intrigued by that particular skill, another was nervously pacing around in his head.

Barry knew his… sound? He could pick him out of a crowd? They were that well acquainted?

Well, yeah, he thought faintly. They were. Because they had been constantly in each other's space for the better part of six months.

A very evil, rather nasty voice in his head pointed out that they were connecting, were already connected. Which was the reason for his sixth sense. Bonding, it hissed.

He pushed it into a dark, dank corner of his mind.

He was no Guide or otherwise inclined.

And yet… he was training his Sentinel. He was focusing the meta part. He was aware of the other man on a level that was beyond what anyone without the empathic predisposition of a Guide should be able to do.

Still, the fact was and always had been that he didn't have those abilities.

xXXx

"We really make a good team," Barry remarked, sounding high on adrenaline, beaming at the man in the full Cold get-up like he was truly happy to see him.

And he was.

Barry wasn't that good a liar and he really had trouble not broadcasting his emotions for the world to see.

"I'm not cut out to be the hero," Len said with a smirk, cold gun resting against one shoulder.

"You saved those people. You did good."

"And how much does that pay again?" he deadpanned.

The Flash was still smiling. "Enough."

Leonard Snart had also never cared. He had never cared about anyone outside of how useful they were to his plans. Partners were interchangeable.

Caring meant opening himself up for a world of loss, pain and risking his neck for those he cared about.

The damnable fact was, he had started caring about The Flash and Barry Allen a long time ago. The whole sentiment had already undergone several changes and caring had morphed into protectiveness.

He holstered the gun, refusing to let himself be guided by those fledgling empathic shivers. "I'm no one's charity case. See ya around, Scarlet."

They both knew that despite the ongoing snarking and little jabs, Cold would come to any scene The Flash was at, would give his input, lend a hand, his talents, his insight. And they both knew that Leonard Snart was still casing possible jobs, running scenarios, visiting possible targets. Len told himself that he did his usual groundwork to keep his mind sharp, to keep an eye out for possible competition, and to know where the really interesting jobs lay. He had a mental list of all the valuable objects of interest, knew how long they would remain in which vault, when they were transferred, and what auction house had which work of art or precious stones up for bidding. He even went as far as sitting through several such bids just to case procedure and look for weak spots.

He was good at that. The best.

And because of that, The Flash was getting a lot of intel he usually wouldn't have.

It never paid, but he did it anyway, sarcastic remarks and sharp little taunts included.

He didn't see or hear anything from his speedster for ten days, which was the longest time both had ever gone without running into each other. Len had started to worry after the first five days of no Barry popping up at one of his places. After the first week he had been very temped to break into the loft, but instead he had just staked it out. The younger man had either adopted a very unhealthy work-life-balance or he didn't sleep at his own place anymore.

Leonard Snart didn't do worry as a rule, but that rule had become obsolete the moment he had gotten involved with Barry Allen.

So he worried.

Enough to run a search pattern across town, trying to pick up a single ping of the other man.

There was none.

And no, that knot in his stomach had nothing to do with Barry's absence either.

In the evening of the tenth day, Barry found him at one of the places Snart liked to frequent for a beer or three, accompanied by a relaxed round of pool or some snacks. Some people knew who he was and couldn't care less, some might have heard of him and didn't care either. It wasn't the seediest of places, filled with criminals and rough-tough brawlers, but it also wasn't one of those hip karaoke places downtown.

Len liked it for exactly that atmosphere. He wouldn't run into the more dangerous clients and associates, he didn't have to fend off hookers or hustlers, and the food was actually quite good.

Barry didn't really stand out that badly, didn't look like he was the hall monitor or TA. The leather jacket was a nice change. Len might have appreciate the outfit for if the speedster didn't look like he was about to keel over. Len had seen him at his best and some of his worst days, be it in a fight, right after, or when Barry Allen had sought him out to decompress later on.

This was bad.

Really bad.

The person meeting his sharp eyes, looked lost, torn, almost so close to the edge he might just stumble over it.

Barry hesitantly sat down, jittery, the air around him spiked with the Speed Force's unrest.

"You look like crap, Scarlet," he remarked, no heat, no mockery in his voice. It was worry. An intense, sharp worry that rose together with an ever sharper protectiveness.

For a moment it was like the air stood still, as if something was about to happen. Raw emotions flitted over the young features, too fast for Len to identify, but incredibly powerful nonetheless. The Speed Force snapped forward, brushing over him without disturbing a single hair and no one but Leonard Snart felt it.

Yeah, this was really bad.

"Not here," he decided.

He just left some bills on the table and walked out, Barry following him like a shadow, uncharacteristically silent.

The silence broke as Snart leaned a hips against the work bench, arms crossed, giving Barry a pointed look.

"She died."

Snart waited tensely, silent, listening, even though his face was a bland mask. "You might want to elaborate a little."

"I got a call. Well, S.T.A.R. Labs did. There was a string of disturbing incidents in Star City. I went there to help and we found it was a woman who had been working at the particle accelerator site when it went off. Her name was Tamara. She was just another victim." Barry screwed his eyes shut, shaking his head. "I wasn't fast enough! Not fast enough!" he yelled.

He paced angrily through the room. Lightning crackled along the lean frame.

"She died because she couldn't handle being… different! She was a meta human. She was like me! She wasn't a criminal! She didn't use her powers to hurt others! She just wanted to be normal and it backfired so badly! I couldn't help her!"

"It's not always your fault," Len heard himself say as Barry fell silent.

"I should have been faster! I could have taken her to the lab, get her down into the Pipeline to isolate her powers!"

"And then what?"

"Talk. Give her a chance to get used to it all. See that she doesn't have to suffer alone!"

"Hand her over to A.R.G.U.S.?"

Barry's expression changed from angry to murderous to lost. "No. She wasn't a criminal. She broke into clinics and pharmacies to get drugs. To make it all go away." His voice wavered. "She needed more each and every time. Nothing really helped. She was losing her mind over the hunger she felt…"

"And she attacked you when you tried to reason with her," Len stated. It was a shot in the dark, but by Barry's expression it was exactly what had happened.

"She was confused!"

"She attacked you."

Green eyes flared with anger and pain. "Not just me. Everyone. She was already on The Arrow's list and I didn't want him to kill her. I wanted her to get the help she needed! We could have developed something to dampen her powers or just neutralize them until we could help! She didn't deserve to be…" Barry's lips thinned. "I can't condone a murder!" he finally spat.

"Of course not," Len murmured, voice low and soothing.

His mind was racing with all the information, especially The Arrow. He knew The Flash and The Arrow knew each other, though he had no idea if both also knew the other's identity. It was possible. The Arrow a vigilante, ruthless, deadly, and not someone Snart would voluntarily cross paths with. Unlike The Flash, who had always been the more interesting opponent.

Len was also reasonable enough to know that pulling jobs like he had done in Central in the past would get him an arrow or a knife stuck in his body in Star City.

He raised his eyebrows as Barry clenched and unclenched his fists. "Did she want to be saved?"

Barry faltered, eyes wide, shining brightly, and he was swallowing hard as if not to throw up. Len held the turbulent gaze.

"Did she, Barry?"

"She hated her powers. She… took off others. Emotions. No matter which. Laughter, tears, anger, pain. She took it and it fed her. She took just a little at first, but then it became an addiction. She killed." His voice faltered, as did his anger. "She drained them. We could have helped. I could have…"

He fell onto the couch, face buried in his hands, shaking but not crying. Len studied the broken looking form. His mind supplied him with a summary of facts, analyzing the data. The meta had been a vampire feeding on emotions. Taking laughter or sorrow from a person sounded harmless, but emotions were important. He had run into a fellow criminal once. Completely without emotions, an automaton, with no mercy, no remorse, no joy. It had made Snart sick to be in the same room with the guy.

Losing all your joy, all your happiness, and also your pain and your ability to express sorrow… that was a shock to the system. He could see how it would drive a normal human being to end their life or to die of the shock of being a blank.

"Did she feed on you, too?" he asked calmly while he dreaded the answer inside.

"She tried. It wasn't more than a second," Barry whispered.

But it had been enough to get him severely off balance emotionally. Len walked over to the seated man, stopping in front of him.

"Barry."

The younger man looked up, eyes filled with self-loathing and blame. Len felt something inside of him almost choke at the sight. Snart could feel the whisper of the Speed Force, hidden behind powerful walls, enveloping this unassuming young man, making him so very special.

He had always quietly admired the sheer determination that burned so brightly inside him. He had an indomitable will, a hope that ran so deep, it seemed to be just another kind of superpower the kid possessed. He really wanted to help people, even those out to hurt or kill him. He wouldn't give up on someone; and he took failure so much harder because of it.

"You're The Flash," he said, holding the green eyes. "The fastest man alive. But there is a limit. And there is a limit to what you can do to help others."

"I…"

He stopped him with a raised hand. "You're a good guy, Barry. You care about people. All people. You are also a strong person. I've never seen a stronger soul. But you are too good. You shoulder blame that's not yours. You're not omnipotent. Accept that you have limits. You can face death and protect the innocents, but you can never save them all. Especially those who don't want to be saved. If you carry all of that on you, it will only slow you down. That's what gets you killed, Barry."

It was the most he had ever said to Scarlet on the topic of his guilt trips. Barry usually worked through it all his own way. Len never asked what bothered him and Barry never talked about it. The few times he did, it had given Snart an insight into the meta and the Sentinel, as well as the meta Sentinel. Not to mention Barry Allen himself, the young man who shouldered more responsibility than he should. He had a team to fall back upon, but he went to Leonard Snart.

"I've failed before," Barry whispered, sounding broken.

"You can't always win."

"I know."

"Yet here you are." There was no mockery in his voice.

"I had nowhere else to go. Sorry. I shouldn't have come."

The smile on his lips was almost soft. "Stay, Scarlet. Just sit your ass back down and stay. She hit you with her powers and that's why you're a little more broken than usual."

There was a flare of anger and indignation in the green eyes, and Len smirked. "I'm not broken!" the younger man snapped.

"Right now? I think you are." Len walked over to the fridge, taking out a beer.

"That's…"

"I know. Just drink it. You might not get the alcohol buzz out of it, but it has vitamins and minerals. Good for you."

Barry took the proffered bottle, a brittle smile on his features.

Len hated to see him so affected. That wasn't his speedster. But mental wounds needed more than a band-aid. He had to work through the guilt, accept his limits. There was nothing anyone could do to help, especially since most of that outbreak was due to getting whammied by the emotion-sucking vampire.

They drank in silence and Barry relaxed after a while, looking tired and worn. He seemed to lean closer without physically moving, his whole body loosened up, muscles no longer so tense.

Snart watched him like a hawk. The meta's influence was visibly disappearing, easing the strain Barry was under.

"Get some shut-eye," he drawled as he walked past the silent man.

Barry jerked as if he had forgotten where he was, blinking a little owlishly. It was testimony to how much he had let go of his guard, how much trust he had put in Len to keep him safe.

Damn. He really didn't need those thoughts.

"I'll head home," he mumbled.

"Sure you can walk?"

"I'm fine."

"Pull the other one, Scarlet."

Barry squared his shoulder, determination chasing away the shadows for a moment. "I can walk home."

Len knew when to not waste his breath. Barry would run home on fumes if he had to, just to prove him wrong.

Which he did.

And no, Snart didn't drive past the speedster's place to check on him. He would deny doing it to his last breath.

He didn't see him for close to a week after that and then only as a red streak in the distance. Len did get two texts, though. One was a simple 'thank you'. The other was an 'I'm good'.

After another week Barry was back again, looking a lot better, the smile reaching his eyes. He wouldn't forget his lost battles, of that Len was sure, but he hadn't let it get to him, pull him into the dark vortex and swallow him.

He had missed having the speedster hanging around his place, spending time together, and while Len had been tempted to break into Barry's apartment, he had respected his decision, given him time and space enough. Scarlet was working through some really heavy stuff and all Len could do was offer an open ear, or a full fridge, as well as every take-out menu of the city on his laptop.

As Barry walked into the warehouse he was currently using as his safehouse, something inside Len relaxed, something inside him unknotting.

"Look what the cat dragged in," he drawled.

Barry grimaced, trying to smooth his unruly hair. He looked windblown but not like he had been in a confrontation. There was a bag from one of the more uppity pasta places in his hands.

"Splurging on the good stuff, Scarlet?" Len chuckled. "That must have blown a hole in your food allowance."

"Got a little piggy bank just for that," Barry shot back.

"Trying to impress me? Not your style."

"Is it working?" was the teasing reply as he plonked the good stuff onto the table.

"Watch it, Scarlet. That's expensive tech."

"It's just bits and pieces."

"Expensive bits and pieces."

Barry unpacked the food and Snart raised his eyebrows at the carbonara. When had he told the speedster what he preferred? There was also garlic bread and what looked like dessert.

"Any of that for me or are you going to hog all the good stuff?"

Barry tossed a prepacked mini cake at him. Len caught it, his smirk almost a smile.

"And here I thought you appreciated me."

"I do. Which is why you get the cake." Barry grinned widely. There was an easy air around him, relaxed and full of playful teasing.

They shared some pretty fantastic tiramisu in the end. Barry stretched out on the couch, hand patting his stomach.

He stayed until he had to get to work.

And Len enjoyed the silent presence immensely.