Endgame SPOILERS!!!
In this prompt, Tony and Pepper aren't married, therefore Morgan doesn't exist (I love you 3000, Morgs♡). This is because I don't want to seem cruel as this won't have the same ending in the movie.
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They did it. They won. But what was the sacrifice to make?
Steve frantically looked around the battle feild, his expression worried instead of victorious.
He ran through the feild, shoving off the other noble warriors who helped them but he didn't have time to thank them. As he got to the clear, he saw Pepper and the others huddled over someone.
'No... no...'
Steve made his way to the small group circle, expecting the worst case scenario. And when he finally got a glimps of the person beneath the others, it was indeed the worst.
"Mr. Stark, we did it, sir." Steve heard Peter say from beside Tony. "Mr. Stark please, sir. Don't leave." As his words fade, Pepper brought the kid to her chest and embraced him, pulling him away from Tony.
All Steve could do was stare at Tony's almost lifeless body. All the guilt and regret came crashing at him at once. Everything that he did and didn't do flowing through his mind. Steve didn't have it in him to come close to him. He couldn't. Cause if he did, his feelings will just come pouring out of his mouth, he didn't want Tony thinking about that as he was... as he--
"I see you are having a self conflict, Captain. But whatever that is, ignore it. This might be the last time you'll ever be with the Man of I-Iron." Thor piped up, his usual roaring voice, though, isn't quite there.
Steve smiled at him, nodding. So he did, he went up to Tony's side, kneeling in front of him. He willed himself not to cry but he couldn't help it. He started choking up as he spoke.
"Tony. Tony, please, look at me?" But Tony was too weak to even move his head. Steve shook his head, looking down in shame at himself, continuing his speech. "Tony, I-I'm so sorry. I want you to know that-that, everything I did to hurt you in any way, I didn't do it intentionally." Steve removed his helmet, placing it in front of them both. "I'm sorry..." Steve set his helmet aside to give some space between the two.
He contimplated about it but he thought, 'Screw it'. Steve shifted his kneeling position, taking small steps towards Tony. He doesn't know when was the last time he was this close with Tony but he didn't care about that as he embraced him.
Steve's tears came flowing down his cheeks continuously. He rocked himself and Tony.
Steve doesn't know how he could live after this. After everything he did. After everything he has said and done to Tony over the years. He thought about it once as an excuse for his feelings, that if he ignored the man himself, it would hurt less. But it turns out, it wasn't, it all brought up to this day.
He held Tony tight until he was pulled back by someone, he doesn't know who, and he didn't care to know. All he cared about right now was the person who started it and ended it all.
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Steve was wrong all those years. Tony wasn't selfish, he cared about everyone. It was just now that Steve realized that. Now that it was too late to tell him that.
He could've had his happy ending if he just listened to his heart more than his brain. He regretted everything. He wanted to make things better, he wants to turn back time. To fix something. To prevent every feud he had with Tony.
He wanted the Civil War erased, he wanted to change the time when Ultron was made. He wanted to be with Tony from the start till the end. He wants to change his history with him.
He wants his happy ending.
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This was it. This was his chance to change everything.
He was only supposed to return the stones but he wanted to change his future, so Steve stayed in the past. He fixed everything with Tony.
From the first time they met, Steve treated him with nothing but love and kindness which was, fortunately, returned. He was happy for the first time in a long time.
Then he prevented their fight during the Civil War. It never happened. And Steve was happy, even the others.
He still helped Bucky, though, get back his memories and still got some help from T'Challa.
All he changed was his relationship with Tony. He didn't do anything else.
Steve smiled at himself, at his future. Unfortunately, though, there was no other way to defeat Thanos than letting Tony use the gauntlet. So he didn't change that.
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Steve was in the present now. He looked around if something has changed. (He knew Tony wasn't coming back but he just had to be sure) Nothing was but he felt something hard against his ring finger.
It was a wedding ring. And ingraved on it were the initials T.S.♡S.S.
'Of course Tony chose his own surname.'
A tear rolled down Steve's eye as he carressed the golden band on his finger.
He was happy. He finally got his happy ending.
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Sorry that this seemed rush but I just was really upset with the end of Endgame (Not that I'm not already happy for Steve and Pegs). I was just so upset that not even once, Cap and Tony hugged. So I fixed the ending :') And I also left out some details cause some of you (for some reason) would read this for spoilers, so I'm sparing you guys some of it.