Natasha spent the night in the tree. She didn't know if he was going to come back and she didn't trust her wobbly knees to carry her all the way back to the Quinjet. Plus, he might follow her, and if he wrecked the jet she didn't know what she would do. She had some safeguards in place—a small tracker on her belt she could activate if needed, a note hidden in her quarters at HQ in a place Steve might find on his third pass or so, a timed alert on her OS if she didn't log in for a long enough period. It had been a while since she had jumped so recklessly into a mission. Scratch that—she had never thrown herself into something so recklessly before.

She lay in the crook of two branches for hours before sleep took her. Her body was exhausted—she felt ashamed. The fight hadn't been long, hadn't even been that difficult. She was just holding so much tension because she was—what, invested? She shook her head, clearing the thought.

Was it worth it to try again? Clearly Bruce—or was it the Hulk?—had tried to transition, tried to swap the lead. Something had stopped him. Natasha remembered the look she saw in his eyes during the struggle, the anguish. She slammed her fist into the tree, just once, holding her self-loathing at bay.

She flashed back to the helicarrier. It felt like decades ago. The first time they had worked together. She had felt her hair stand on end even being in the same room with him. Everybody treated him like a ticking time bomb, the uncertainty and fear a price they had to pay for Banner's genius. Other than Tony, of course. He was the asshole unafraid to poke the sleeping bear, to play with fire. He was also the only one who had treated Bruce like a human and actually worked with him. She couldn't imagine how that must have made him feel, to have everyone so scared. And yet, she had been.

Terror, when they dropped through the floor of the lab after Clint had attacked under Loki's possession. How she had been trapped by a metal girder, watching Bruce fight within himself. She had been panicked. She felt the same terror lurk now in her stomach. In the years since, she had come to know him, to care for him, to trust that he wouldn't lose his cool. She saw everything he did to remain calm, to breeze through, to maintain the tightest, strictest control possible over every aspect of himself that made him human.

Those were the parts she had tried to keep whole. Their missions to flush out Hydra had been instrumental in that. He didn't even want to go at the beginning, but his presence made the difference against heavy artillery. He had been miserable for those initial missions, recon and probing. He would sit anxiously on the jet as they traversed the globe, turned inside himself, miserable. He never wanted to talk to them, never offered so much as a comment on anything unless it was related to his lab work with Tony.

The first time they took a smaller base and he stayed back in the jet, it seemed to be a relief to everybody on the team. No unpredictable green monster in the field, and no need to budget thirty or forty minutes to take him down afterward. They had gotten back on the jet and on the flight back, he was an entirely different person.

He joked with Tony about some nuclear undergraduate disaster, possibly the first time Nat had ever heard him laugh. He talked with the whole team rather than sitting with his head hanging, wringing his hands. For the first time, he wasn't beating himself up over what had happened—or almost had. That warm, confident, joking personality was so starkly different from the anxious wreck Natasha had always seen him as before. She wanted to see more of it—and their missions with him going green seemed to be counter to that goal.

That was what inspired her to suggest the meditation. She guided him through it every morning at Stark Tower—Avengers tower, now. Their days were spent in strategy and research for the next raid with the whole team, but every morning, they had a safe space, an hour alone together. The association had built slowly; her voice, soothing him, tied to the breathwork and peace of the dimmed-out yoga studio on the 44th floor.

It was nearly two years after the Battle of New York that the breathwork came out into the field with them for the first time. It was a base in Austria, in the foothills of the Alps. The base had some heavy missile launchers that they needed something big and indestructible to go destroy—there were too many for Tony to fly in solo, their range was too far for Clint, and Thor was taking care of the tanks down below with Steve.

Bruce had been his regular anxious self on the way over until Natasha sat with him and started the breathwork. He had tried to stop her, claimed that calming him down ahead of time might mean he couldn't get mad enough when the time came.

"Performance anxiety?" she had teased him. The shade of red he turned almost matched her hair.

It had worked, though. Rather than wringing his hands and twisting his stomach in knots, he had focused on her right up until the moment he ran into gunfire, triggering the Hulk with danger rather than rage. Afterwards, Nat had approached him on the stone bulwark of the base where he was smashing one of the missile launchers into bits.

The Hulk had roared at her and she was ready to signal Clint to fire his tranq arrow from two hundred yards away where he was lying ready. He told her later he nearly did, based off that roar alone—the tranquilizers Bruce and Tony had developed together were effective, but still took longer to kick in than they should have, and Clint would need the extra moment for them to save Nat. But the roar hadn't turned into a charge. The Hulk seemed bewildered that someone would approach him in peace. He let go surprisingly quickly, and for the first time, Natasha was able to go to Bruce and hold him when he came down, shivering and exhausted.

He told her afterwards he didn't like that, didn't like her seeing him when he came down. She hadn't pushed it, allowing him to stagger off and take a few moments to collect himself every time after that.

And slowly, the bond grew. He trusted her with the Hulk. Slowly, he trusted all of them, mission by mission, month by month. They had a flow, a rhythm, one that was built on the mutual trust between him and Natasha. And never did she let on that that trust felt like a bowstring, pulled taut between them, ready to release and launch them into a terrifying and unknown territory at any second. The confusing mix of professional and personal was hard to navigate.

She remembered standing close to him at Barton's house after Wanda had decimated them that first time. The smell of his aftershave, his curly hair still dripping from his shower, his hand covering hers next to his face. . . The memory seemed to open a gaping hole in her, allowing her fear to penetrate her mind. The weakness she had allowed herself was coming back to bite her. She slept, finally, but it was interrupted, tense sleep.

The morning dawned with raucous noise all around her—monkeys hooting, insects slithering and buzzing and chirping all around. Nat stood and stretched, wrenching her neck through her range of motion, ignoring the tightness and spasms and pain. No time for that.

In the light of day, she could see the trail of wreckage from where they had fought the night before and where the Hulk had run afterwards. She paused. She could follow the destruction from their chase out to the beach, track back up north to where her Quinjet and supplies were. Or she could follow the other trail, off to wherever he may be, and try again.

She lowered herself down the branches of the tree she had spent the night in and then dropped the last few meters to the ground. She landed with a groan, then walked once around the massive tree. It was a lucky find, strong and set apart enough from the foliage around it that she had been truly protected. She knocked against the trunk once. It hurt her knuckle—the wood was hard and resonant.

She saw a small trickle of water nearby and finally allowed herself to feel her thirst—it would have been unproductive before, when there was nothing she could do about it. She pressed a button on her bracelet and a small compartment in her belt opened up, freeing a small water purifying tablet. She grabbed a wide green leaf from a plant nearby and rolled it into a cone, dipping it into the small stream and allowing it to fill before dropping the tiny tablet in and drinking deeply. She'd have to thank Stark for some of the additions he'd made to her suit, as much as she hated to admit it.

The water was enough of a respite to convince her—she had to find Bruce. Or whatever was left of him. Other creature comforts could wait until she made sure he was ok.

She set off down the pathway of wreckage; splintered trees and deep muddy footprints making an easy trail for her to follow. He had run straight towards the center of the island before veering right, back towards the western shore. Even with him having paved the way for her, the going was painfully slow, thick underbrush and deep mud making every step painstaking. After an hour, Natasha emerged to the beach once more, further south yet still on the western face of the island. She shielded her eyes from the bright sun overhead and scanned the beach. There—off to her right, she saw a spindly structure with some sort of shape in front. The bright sunlight was making it quiver and dance in her eyes, so she walked closer, sticking to the tree line.

It was an old beach cabana, abandoned by the looks of it, lifted on stilts over the water, with a ramp up from the beach. He was lying in front of it, prone.

Natasha fought her urge to run to him and make sure he was ok. She would have had no issue doing that before Sokovia. It had been almost a year now, and it seemed like some things had changed.

She sat in the cover of the tree line and watched him, thinking. A mango fell from a tree nearby with a thud. Nat retrieved it from the sand, pulled out one of her knives and started cutting off bite sized chunks to snack on while she waited.

Should she approach again? He had started to come down last night. Even after failing, he didn't try to hurt her again. He didn't try to stick around, either. He left. He fled.

She knew she had to try. Why was she here otherwise? Still, she waited. She couldn't force herself to move from her spot, from relative safety. She grew more concerned as the day went on and he didn't move. Finally, in the early evening, he roused himself. He rose and stretched and walked into the ocean, letting out a hiss as he waded into the water. When he was at waist depth, he dived under the surface, emerging a moment later with a fistful of something—seaweed? Fish? Both.

Nat watched impassively as he shoved it in his mouth, chewing and swallowing easily. If anything, she was relieved he had found a way to eat. She hoped he hadn't been drinking salt water. She didn't know what that would do to Bruce when he came back.

After diving in twice more, the Hulk sat on the shore and began itching. He groaned as he scratched, clearly in pain but unable to stop. Natasha cringed. She had been about ready to approach and make herself known, but his obvious frustration kept her at bay.

Eventually he stopped, sitting and facing the water. He didn't move, didn't speak, didn't scan the horizon looking for anything or anyone. It was disconcerting. Nat wasn't used to seeing a peaceful, passive Hulk. He was usually only around when shit hit the fan.

The moment seemed as calm as it might get, so Nat slipped away from the trees and out onto the sand. He didn't see her until she was only fifteen yards away. She held her hands up and stopped in her tracks.

"I don't want to fight you," she began hesitantly. "I don't think you want to fight me either."

The Hulk turned and looked her up and down. He grunted once, but didn't move from his spot.

"It's been a while. Things are different now, aren't they? I'm not going to pretend they aren't. I'm not that dumb." she looked him in the eye. She took a step towards him and he didn't react, didn't move. Any closer and this would be a suicide mission if it didn't work. Every warning bell in her body was going off, yet Nat stepped closer anyways.

"I missed you," she continued.

The Hulk let out a huff of air.

"I know. I didn't deserve to. Sorry."

He grunted, stepping away from her. Nat continued creeping forward. He stopped beneath the bamboo floor of the cabana.

"Hey big guy," she murmured.

He let out a rumbling growl, then plopped to the ground. She stood and watched, but he didn't move again. She approached, holding her hand out. He wasn't even looking at her, just dejectedly looking at his feet, his head hanging low. She walked around his legs and ever so gently laid her hand on his arm—the skin was broken and open, oozing green liquid. She forced herself to not move her hand away, to not think about how he had gotten like that. He flinched at the touch. He turned away from her, and even as he shifted away she watched the transformation begin.

His tattered, nearly destroyed pants seemed to grow around him. His shoulders fell forward, his body toppling over in the sand. She watched it finish, the monster seeming to roll in on himself until all that was left was Bruce, curled in fetal position, facing away from her. She waited a second to make sure it had really happened, it was really him, it wasn't some trick by the monster about to return. It wasn't.

She rushed forward and knelt beside him, hesitating before putting a hand on his shoulder. He flinched, then let out a wracking sob, gasping for air. The skin on his back was mottled with sores, open and oozing a clear liquid. Some of them bled.

"Bruce," she breathed, taking in the sight of him. He groaned, rolling away from her over onto his knees.

"You're scaring me here," she touched his back and he cringed, flopping onto his side and weakly slapping at her hand.

"Get away," he moaned.

"Fat chance."

She inspected the rest of his body. What she saw was terrifying—the sores were on his back, his chest, at his elbows and knees, trailing up and down his arms and legs. His feet were the worst, split open, bloody and raw, She had never seen so much damage come back with him into his human form before. The Hulk usually bore the brunt of it, an impenetrable, indestructible fortress. The fact that he had been bleeding too—she had always watched him heal so quickly. How was the damage so extensive?

Before she had a chance to look closer, Bruce doubled over and heaved, then heaved again. Nothing came up, but a guttural, clicking sound deep inside him made it seem as though something definitely needed to. He laid there a moment, then heaved again, again with no result.

"Bruce, I need to get you to the jet," she spoke calmly, trying not to let on how frightened she was. Wounds she could handle, but something internal? That was a whole other story. She had no idea what the Hulk had put in his body.

"Leave me alone," Bruce whispered, trying to crawl away. He made it no more than a foot before slumping down again, groaning. Natasha recalculated quickly in her head. No way was he going to make it to the jet—she'd have to hike there and fly it back. How far of a hike was it? Would he make it that long on his own?

"Ok, I'm going to go get some supplies to patch you up," she began.

"Nat," he whispered.

"Yes?"

"Go away."

She sat back on her heels and bit her lip.

"I deserve that," she acquiesced. "Now honestly, let's get you up into that cabana," She reached out to help him stand, but he flung an elbow out to try and stop her. It was almost comical, so slow and weak. Nat leaned slightly to the side so it brushed off her hip.

"Bruce, let me get you into the cabana. We can talk then."

He tried to respond but heaved again instead. A gurgling noise came from his throat and he began coughing viciously. Nat watched helplessly as he hacked up a pink piece of something—she didn't want to know what. He hacked again and a small spatter of blood hit the sand next to his head.

"Ok, I'm done asking nicely," Natasha linked her arms under his armpits and lifted. She half-dragged him up the ramp into the cabana, his feet stumbling and flopping uselessly beneath him. She was worried by how light he was too—the Hulk had seemed healthy, why was Bruce so skinny?

She was surprised when she got to the doorway of the cabana to see a giant nest of palm fronds, and reeds in the corner. She didn't know why—it made sense the Hulk would sleep there. It was away from threats and sheltered from the elements, which would be ideal for the big guy. She settled Bruce down in the middle of the hulk-sized bed, stepping back worriedly and watching him curl in on himself, pathetically small in the oversized space. He shivered once despite the tropical air. She jumped from the window down to the beach below and grabbed the ruined pants from the sand. They were beyond repair, but they'd do for cover until she had the jet there. When she got back up into the cabana, Bruce had hacked up some more pink stuff.

She wasted no time, covering him with the disgusting pants, feeling his forehead once, half to get his temperature and half in a vague need to convince herself he was real, and then took off north up the beach. Before she had planned on walking, but this was an emergency. She shook her head and settled into a ground covering yet sustainable jog. She hated jogging. She hated the thought of losing him more.

She was back in just over an hour, still huffing in her seat as she settled the Quinjet down onto the sand about thirty meters from the cabana. She grabbed the first aid kit from inside. Back inside the cabana Bruce had made more of a mess—he was half out of the bedding, a small puddle of bile and pink material interspersed with small amounts of blood next to him. He hunched on the floor, his eyes clenched shut, sweating ferociously.

"Oh c'mon now, why'd you go moving on me?" Nat joked half-heartedly. She set down the kit and opened it. She grabbed a long metal rod from inside—one of Tony's newer inventions inspired by Dr. Cho Nat clicked it on and then swept the wand over Bruce's midsection.

"Subject movement detected. Please hold still." F.R.I.D.A.Y's voice cascaded from the instrument. Bruce stopped moving. "Multiple skin lesions detected."

"Yeah, got that much, what's going on inside though," Nat muttered impatiently.

"Major obstructions detected in small intestine, large intestine, and stomach. Minor perforations. Performing diagnostics."

Nat held her breath and watched Bruce convulse once more.

"Treatment rendered. Swallow this." The instrument opened at the base near Natasha's hand and a small pill came out, held on a tiny lever.

"Don't you think he's kind of past the Tylenol stage of this one?" Nat remarked caustically.

"This is a nano-robot intended to artificially metabolize obstructions with minimal damage to bodily systems. It will disperse nano-particles to facilitate internal repairs." F.R.I.D.A.Y's calculated voice had never sounded so good.

"Hear that big guy? You're gonna be ok," Nat smiled as she plucked the pill from the wand. She held it in front of Bruce's face, but his eyes were still glued shut. "You gotta swallow it."

Bruce shook his head noiselessly.

"So what, you're tryna die on me?"

"Shoulda left—" he broke down hacking. Another pink piece of something came up—Natasha was increasingly worried that he was coughing up parts of his own lung.

"Take the fucking pill, Banner."

He waited for a second before shoving his hand out in front of him. Nat placed the pill in his palm and watched as he tossed it in his mouth and swallowed with great effort.

He rolled over back into the center of the mattress and curled up, facing away from her, showing her his skinny, sore-covered back. The vertebra stood out on his spine like braille.

She watched him like that for hours as the sun set. Slowly his breathing calmed. He didn't retch again. His skin warmed from the dusky grey color it had been. He was out cold. Nat took the chance to pop open the medical kit and apply some anti-bacterial ointment to the worst of the sores that were in reach. She didn't want to touch him without consent, but they were gaping and open and looked like they were begging for infection, especially the ones on his feet. She'd have to try and clean them later, when the pain of antiseptic wouldn't wake him.

Her ministrations done, she returned the kit to the jet and retrieved some clothes for him—just a few things she had set aside in one of the cargo compartments. Just in case.

Back in the cabana, she used an old towel to wipe away what he had coughed up and laid the clothes out next to him, a peace offering of modesty and respect.

She returned to the jet, ate a pre-prepared ration, and then tried to decide where to sleep. If she was in the jet, there was no promise he wouldn't try to slip out once he woke up. His feet would make it near impossible, but she wouldn't put it past him to try and hurt himself anyways. He seemed so upset with her, she didn't want to enter his space and sleep in the cabana either.

She decided on the front stoop, where the ramp led up to the cabana from the beach. She grabbed her sleeping roll and headed up. He'd have to step over her to get down to the beach, and she didn't think he was up for that.

The moon overhead was nearly full. She looked at it, examining its craters as she drifted off.