A/N: Sorry I've been MIA recently, school got really rough and I didn't have any time to write. Hopefully now that it's summer, I can write a little bit more consistently. If you are here for Heartbroken or Replaced, don't worry. I am working on updates for those as we speak. For now, here's this Endgame fic that I couldn't get out of my head.

This is an AU where Peter didn't get snapped away in the initial snap.

Endgame spoilers ahead.

Natasha Romanoff doesn't scare easily. Everyone knew that. But tonight, Natasha jolted awake, sweating and breathing hard. She tried to take a deep breath to calm herself down, but it took a minute for her to steady her heart rate.

In her nightmare, Peter and Steve had been snapped away along with the others. Her worst fear had come into fruition. Surprisingly, Nat had found herself growing fond of the little spider who always made stupid jokes at the worst times. But even if he did employ the worst dad jokes over the comms during missions, he helped bring a light to the team which no other Avenger possessed.

Natasha had always wanted kids, but much to her chagrin, her past life hadn't been so kind as to allow her that privilege. She thought back fondly to a time when she was with Clint, Laura, and their kids.

The Barton Household

"Auntie Nat! Auntie Nat!" Natasha heard Lila screaming before she saw the girl charging from around the corner. There had been a lull in the action, so Clint and Laura had invited her over. She hadn't seen Laura or the kids in a while, so she gladly accepted the offer.

Nat smiled wide as Lila ran towards her and lifted her high into the air, swinging her in a circle. While she had her back turned, Cooper ran up and crashed into her legs, holding on tight. "We haven't seen you in FOREVER!"

Natasha laughed as she set Lila down and wrapped her arms around Cooper. "Yeah, I might have missed you guys a little…" Laura walked slowly towards Nat with little Nathaniel in her arms, and gave her a warm hug, trying not to smush Nathaniel in the process.

The hard and intimidating Black Widow cooed softly as she pinched Nathaniel's cheek. "You were supposed to be a little Natasha, but I suppose you're cute enough for me to let that one slide." Laura chuckled softly, and led everyone toward the dining room where Clint was waiting.

He smiled in greeting when he saw her. Dinner carried on mostly with Clint and Laura watching Nat converse animatedly with the kids. Once dinner was finished and Nat had tucked the kids in, she walked back downstairs with a soft smile, a rare look for the lethal soldier.

Laura and Clint joined her on the couch and Laura placed her hand on Nat's leg. "Natasha, I think you would make a great mother one day… Are you going to try for kids? I know you have an abnormally busy life, and you may feel like motherhood isn't for you, but I really feel like it suits you."

Natasha's grin fell a little. "Standard Red Room Procedure… We get sterilized on graduation day. I can't have kids."

Laura immediately backtracked and went to apologize but Natasha cut her off. "Don't worry about it, Laura. Seriously. Cooper, Lila, and Nate are all I need. And one day if I change my mind, I could always surrogate or adopt."

The three fell into a companionable silence by the fire. Clint and Laura didn't see the single tear that ran down Nat's cheek.

Back at the Avengers Compound

Natasha shook herself from the memory and got properly dressed. As soon as she walked into the kitchen, she was greeted with a smile.

"Hey, Nat! I was wondering if you'd be down soon. I was hoping you would, so I made you something. It's just a peanut butter and jelly sandwich. I don't know if you like those or if you are even hungry, but I was hoping that you-"

Natasha cut him off by pulling him into a hug. Peter tensed at first, but immediately relaxed into the embrace. When he pulled away, he saw tears in the Black Widow's eyes. Peter had noticed how much of a toll Thanos had taken on the woman. She looked so worn down; so much older now. Her face had permanent stress lines, and it seemed her body sagged… She was a shell of her former self.

Peter leaned back and tentatively questioned. "Was it another nightmare?" Natasha's silence was all the confirmation he needed. It wasn't the first time she had this nightmare, and Peter knew it. He pulled her back into another hug. "I'm okay, Nat. You can't get rid of me that easily."

He said it full well knowing that, in fact, it would be easy to get rid of Peter. All it would take is a snap of the fingers. And he also knew that it was just a stroke of luck, a 50% chance, that he was standing there at that moment. He whispered reassuringly. "I'm not going anywhere."

Natasha pulled back and examined the boy. He had been with her since the moment that he, Tony, and Nebula had returned. Peter had initially wanted to stay with Tony, but Tony had pushed everyone away. He went off with Pepper to start a family, and had been MIA since. Sometimes Tony would send the occasional "Hey, kid. Just checking up on you." But other than that, Peter had found comfort in someone else.

Nat knew that if Peter weren't here, she wouldn't have made it this far. He was the only thing left that was keeping her going.

Even Steve left. He would come visit her once a week, but he never stayed. It wasn't the same.

It would never be the same.

The two soldiers had seen too much loss, and Nat was afraid that the snap had been the last straw. The team was gone, and Steve felt that he needed to fix himself before he could even begin to help fix everything else.

So Natasha was left to pick up the pieces. She had held strong and led the remaining Avengers in their search for Thanos. But everything was wearing her down. Peter was the only one who had never left. The motherly and optimistic part of her wanted to think it was because Peter cared about her.

But the cynical part of her told her that Peter only stayed because he had nowhere else to go. Aunt May and the rest of his friends from school had fallen victim to the snap, and Tony wasn't taking any visitors. So Peter was left to stay with her.

Now if she had asked Peter, he would have told her that he was there because he wanted to be and not because he had to be. But Natasha Romanoff never asks those questions. She tries not to get attached to anyone.

Unfortunately for her, it was too late. The boy had immediately found a soft spot in her heart, even before the snap. And after everything Peter had done for her since the snap, he wasn't going to be leaving that soft spot anytime soon.

Peter was like a son to her now. And she'd be damned if anything happened to him.

Nat snapped out of her trance-like state, and reached for the sandwich Peter had made. Every minute he wasn't sleeping or taking care of Nat, Peter was constantly in the lab working on a way to bring the others back. He hadn't found anything conclusive yet, but he felt as though he was getting close.

He and Nat settled into their usual daily routine of him typing away on a keyboard trying to research ways to potentially reverse the snap, while she contacted the remaining members of the team from a desk three feet away.

The two had grown so close over the last five years. They were inseparable now.

They were family.

Peter frowned as he saw Natasha slam the communicator down on the desk. He had zoned out so he didn't know what the call was about, but he still had an inkling.

"Is it Clint?"

At the mention of his name, Natasha slumped into her chair and put her head in her hands. She never broke down in front of her team. She needed to be strong and she needed to be the leader. But with Peter, it was different.

It was always different with him. Safe.

Peter quickly vaulted over the desk and immediately wrapped his arms around her. He just stayed there like that until his Spidey Senses picked up Steve walking into the compound. He cleared his throat and warned Nat, and he watched as her demeanor immediately changed.

She sat straight up in the chair, once again shouldering the burden of the entire world alone. He couldn't even tell she had been crying just moments before. Peter shook his head with worry. If she continued down this path, the weight of the world would crush her.

He was just about to say something when Steve poked his head into the room. He was holding up a bag. "I brought some take out. Anyone hungry?" Peter watched in dismay as Natasha plastered on a smile, refusing to show weakness to anyone else. Refusing to be helped.

Nat walked over and took the bag from him. "You've always known how to cheer me up, Rogers." Steve wrapped an arm around her shoulders as they walked back to the tables together. "So how's everything? Any new developments?"

Natasha smiled dryly, letting a hint of sadness creep into her eyes. "Not since you asked last week. How about you, Cap? Saving the world one group therapy session at a time?" Steve chuckled, but his heart wasn't really in it. "Yeah, well… Just wishing I could do more."

Peter was about to cut in when his hearing picked up a disturbance outside. He shushed the two and moved to the surveillance monitors.

And standing outside was his fellow bug-themed superhero. One that he didn't think he'd ever see again.

Scott Lang.

Minutes Before the Time Heist

Natasha had tried, but she couldn't convince Clint to come back. He had gone down a dark path, and no matter what she said, he couldn't come back out of it. She was disappointed, but figured that if the plan went right, Clint would go back to the way he used to be. So she had stood tall and left him standing him in the rain, resolving to get his family back.

Before each mission, she and her former best friend would always gear up together. But since he hadn't come back with her, she went to go check on the little spider instead. She knocked softly and cracked the door open. Peter whipped around, looking up from the picture in his hand.

Nat came in and sat next to him, glancing at the image. It was a worn down photo of Peter and Aunt May at one of his science fairs, a week before the mission that sent everything to hell. She sighed as she looked into his eyes and saw the deep loss that had settled there.

No one deserved to lose as much as Peter had, but it was even worse since he was just a kid. She had watched him mature over the past five years into a young adult, but the haunted look of loss never left his youthful eyes.

"Peter, remember that promise I made to you years ago? When you had first gotten back with Tony and Nebula?" Peter just nodded. "I swore to you that I would find a way, Peter. I told you that I was going to get her back, or I was going to die trying. I still stand by that. Tonight when it's all over, you'll get to eat a PB&J with her instead of boring old me." She gave a small teasing smile. "But I'll probably end up crashing the party anyways."

Peter returned the fleeting smile with one of his own. "You won't have to crash the party, Nat. After everything you've done for me, I think it goes without saying that you're invited." Natasha let out a small chuckle, and it filled Peter's heart. It was so rare that he ever saw Nat smile or laugh, especially in the last five years, but her soft side always came out when it came to him. It was one of the things he was most proud of.

"Let me suit up, and then we'll head out to meet the rest of the team." Natasha nodded and once he was finished, they left towards the center of the complex. Tony saw them approach and walked over to meet them.

"Glad to see that the suit I made for you is still in one piece. Thought that by now, you would have definitely messed it up." Peter smiled as he pulled Tony in for a tight hug. They hadn't seen each other in person for the better part of the last five years, and Peter had admittedly missed him.

Tony clasped arms with Nat. "One last rodeo, huh?" Natasha gave him a firm nod. "That's the hope." She studied his worn out eyes, tired from all the fighting. But she could also see a hint of a happier place in there. She was grateful that at least one of them could have a family. "I'm glad you came, Tony. I know you didn't have to, and I wouldn't have faulted you if you didn't show. So thank you."

"Well, I wasn't about to let the rest of you get the glory of saving the world without me. My ego wouldn't be able to handle it." Nat smacked him teasingly on the arm. The three of them walked up to the rest of the team. Cap gave his speech to rally the troops, and Natasha mentally prepared herself for the beginning of the end.

They all split into their respective groups. Tony eyed her standing next to Peter. "You better bring the kid back in one piece, Widow. Keep him safe." He had said it as a joke, but everyone could hear the hint of seriousness underlying his tone.

Natasha stared at the man straight in the eye.

"Don't worry, Stark. You'll see him in a second. I promise."

Vormir

Peter watched as Natasha gently set the jet down on the surface of Vormir, readying himself for whatever challenge they would face. "It makes sense that they would send us here, Nat." In all of his childlike innocence, Natasha couldn't resist a smile.

"Yeah? And why's that?"

They headed down the ramp and onto the floor. "Well, we don't know what we're going to find. We just know that this is the place where we need to get the orange rock thing. So, I was thinking. It makes sense to send the two coolest Avengers to the planet with the coolest name. And it also makes sense that they would send the two strongest to the one challenge that's unknown. Don't you think?"

Natasha turned around and smacked his shoulder lightheartedly. "You're unbelievable, you know that? We're on a mission that will decide the fate of the world and you're talking about how cool the name Vormir sounds."

Peter laughed as they began trekking up towards the peak of the mountain. "Hey, no need to get all violent! I'm just saying… I bet you that we'll be the fastest ones back to the complex. Team Spider will always be the best team. No one can beat Mama Spider and Little Spider."

"Peter, the machine is programmed to bring us all back at the same time… That's physically impossible." Peter rolled his eyes. "I know, Nat. I helped program it. What's it like being a kid's personal killjoy? Does it ever get boring?"

Natasha laughed lightly. "You don't get to pull that card. You're not a kid anymore." She immediately sobered up. "You haven't been one for awhile."

Peter looked at his partner as they neared the top of the peak. "Well, in any case, I couldn't have asked for anyone better to have raised me for the last five years. If it weren't for you, I'd be lost. There's no one I'd rather have watching my back."

They finally reached the top and Natasha pulled him in for a tight hug. She whispered. "Thank you for being there for me, Peter. You were there when no one else was. No matter what happens today, I promise I won't let anything happen to you."

Peter nodded and together, they turned around to confront the ugly red demon that had begun to float towards them. An eerie wind settled upon the trio as Red Skull spoke.

"Natalia Alianovna Romanova, son of Ivan. Peter Benjamin Parker… I see you've come to receive the Soul Stone." Natasha recoiled slightly at the revelation that this being knew her father's name, but tried not to let the shock show.

"Just tell us what we have to do, who we have to fight. As soon as we get the stone, we'll be out of your way." Red Skull just laughed at that. "You don't even know, do you?"

Peter frowned. "Know what?"

"The Soul Stone is not something you fight for. It is a rite of sacrifice. A soul for a soul. Your team didn't tell you? Nebula… so unpredictable, that one. I thought she would have at least informed you, since one of you would not be coming back. Never mind that fact, this makes for a nice plot twist."

Natasha clenched her jaw as she began inching herself protectively in front of Peter. "What are you talking about?"

"In order to obtain the Soul Stone, one of you must trade something you love. It's exactly as I said before. A soul for a soul." Red Skull smiled just a little bit wider. "In case you don't understand, allow me to elaborate and put it into simpler terms… One of you is not coming back."

Natasha glanced backward as the realization dawned on Peter, just one second too late. At that moment without hesitation, Natasha took off towards the edge of the cliff. Peter was shaken out of his state of shock, realizing all too soon what Nat was about to do.

She was the closest thing he had ever had to a mom, since the death of Mary Parker all those years back. And he'd be damned if anything happened to her on his watch. He immediately launched out his arm and caught her with a web, yanking her backwards and halting her progress. He vaulted straight over the top of her and started running for the edge himself.

Natasha hit the ground hard, but didn't have any time to register the pain, as she saw her practically adopted child start hurtling towards the edge. She rolled to her feet and immediately sent out three Widow's Bites, connecting every single one with the back of his suit. Because of the metallic installments Stark had made all those years back, the electricity's power increased tenfold.

Peter immediately fell from the pain, and shook his head to clear out the cobwebs. When his vision finally cleared, he watched as Nat threw herself straight over the ledge. His body was moving before his mind was even able to process the horror of what had just happened. He felt himself go over the edge, and he dove straight down until he finally felt his arms enclose around Natasha.

They slammed into the wall and the impact caused his grip to loosen slightly. Natasha slipped down until it was only their hands keeping them connected. Peter latched on with his gloves, knowing that Nat wouldn't be able to fall if he stuck his hand to hers. He planted his feet onto the cliff face, and slammed his other hand against the wall.

They weren't in danger of falling because Peter had stuck them to the wall, but he wasn't able to climb up either. Without both hands, he wouldn't be able to scale back up the wall. The thought briefly crossed his mind to use the metallic legs from the back of his suit that Stark had built in. But when he tried to activate them, he found that Natasha's Widow's Bites from earlier had fried that entire section of his suit.

Natasha looked up at him with a look that had never been directed at him before.

Her eyes were cold.

Peter was almost shocked at the sight of it. He had seen that look on her face many times throughout the years, but it had never been directed at him. He realized that she was trying to erase all form of affection from her face. She was trying to make him hate her so that he'd let go.

Nat stared him directly in the eyes, harsh and unforgiving. "Let go of me, Spiderman."

Peter narrowed his eyes, as his mask folded back into his suit, revealing his face. "Good luck with that one. You and I both know I am never letting you go. If one of us is falling, it's going to be me."

The trick with the mask had the intended effect. Upon seeing his face and not just his suit, Natasha's eyes immediately softened and her grip on his hand tightened. "Peter, please. We both know that there's no way you could drop without me falling too. If I fall, you can just climb back up. But if you fall, I won't be able to get back up. It's not logical."

She saw his eyes flicker with the painful realization that she was right. "You have so much left ahead of you. You've done so much good, and you can do more. You deserve this."

Peter's heart ached. She thought he deserved to live more than her, simply because of the red on her ledger. They were both at a crossroads, neither willing to let the other fall. That's what happens when two spiders end up on the same web.

Natasha continued to plead with him. "Peter, the team needs you and the team needs the stone. We both know this only ends one way." Peter shook his head adamantly. "No, Natasha. I'm going to find a way. I promised myself I'd bring you home safe. So we'll figure it out. I'll get us both back to the top, and we'll find another way. Please."

The older woman gave him a soft smile. "You can't take me home, Peter. Home isn't a place… At least it's not for me. The past five years, the team has been everything to me. You have been everything to me. Peter, you can't take me home; you are my home. I promised you that you'd see Aunt May again. I promised Tony that I'd get you back safe. But most importantly, I promised you that I'd get you back safe. And I never break my promises."

Peter's eyes welled up with the realization that she was not going to back down from this. His voice broke as he pleaded with her. "Natasha, I'm begging. Let me save you. Please. I can't… I can't do this without you. Not anymore, not after everything we've been through. I'll never forgive myself if I let you go through with this. It's not worth it. Nothing will ever be worth your life, Nat. Not to me."

"One life for half the world. Mine for 3.5 billion people… Sounds pretty worth it to me." Natasha smiled tearfully at the boy she had come to love. She was so proud of the man he had become, and was happy that she was able to be in his life. That she was able to make it better. Because all the kid deserved was happiness, and she'd die before she let anyone take that away from him.

She used Peter's legs as footholds and climbed up his back so they were eye-level, grunting from the effort. "Peter Parker, you listen to me. I couldn't be prouder of who you've become. Despite every damned thing on this earth trying to bring you down, you've persevered and still manage to be a hero. I don't know how the hell you do it. I've been trying to figure out the whole hero thing since I joined SHIELD. It just hasn't stuck. You've been my rock for the past five years, and you've stuck by me, even through my worst days. I never asked that of you. You've got the biggest heart I've ever seen, so don't you dare let it go to waste. I won't let you."

Peter was overcome with emotion. "Please. Don't do this. I love you. We can find a different way. Please."

Natasha was whispering, the force of all the emotions overwhelming her. Tears streaked down her face as she realized this would be the last time she saw his face. His tousled hair. His hopeful eyes that remained optimistic even though they were worn down by loss.

"My little spiderling, never forget how much I love you. You are my home. And you always will be. So don't worry about getting me home, okay? Because I already am. I have been ever since the day I met you. I love you so much, маленький паук. Now go save the world."

And with that, she reached around and tenderly kiss his forehead. When she pulled away, she wrapped him in one last embrace, resting her head on his strong shoulders. Peter's hand came up to return the hug. They stayed like that until Natasha finally felt him relax a little. And that's when she found her window. She planted her feet and pushed as hard as she could off the cliff face, falling straight into a dive so that Peter wouldn't be able to catch her.

Peter watched, broken, as the last mom he had left give her life to save him. And then all he saw was darkness.

He sat up with a start, immediately looking around for Natasha. Hoping against all hope that it was just a dream. That he would wake up on the jet on the way to Vormir, and he would be able to try again. Peter felt his heart shatter all over again when he didn't find her. He felt something warm in his hand, and looked down to find the cursed stone materializing. It seemed to glow and radiate with power as each tear splashed down onto it. Like it was feeding off of his grief.

Peter had half a mind to crush it right then and there. His grief-stricken mind was furious with the stone, and what it had just taken away from him. But he wouldn't let Nat's sacrifice go to waste. He was going to use that stone and find Thanos, and he was going to make him suffer.

Mind made up, he found himself sucked into the darkness once more. This time, he awoke to find himself tumbling through the quantum zone. When he finally came out and found the rest of his team, he stood frozen in shock. Frozen with the realization that he would have to tell them that he failed. He brought back the stone, but at what cost?

Upon seeing the last arrival, the Avengers began hugging and clapping each other on the back. Celebrating their victory. Tony finally peeled off to go congratulate Peter, when he finally noticed. "Peter, where's Nat?"

Every single head in the compound whipped around at the question, and watched as the boy fell to his knees. He whispered two words, but it was enough to break everyone.

"She's gone."

And there in front of everyone, Peter broke down and sobbed. He cried because he would never get to see Natasha again. The person who had taken him in, and taken care of him. The person who had been a mother to him. He would never see her again.

Because even though he was Nat's home, she was his too. And Peter would never be the same knowing that she gave her life so that he wouldn't have to.