You had insisted—no, gently coerced—Bucky to attend the costume party Sam had organized back in Louisiana with his family. At first, Bucky was reluctant, grumbling about the whole idea, but you were persistent. It was the perfect chance for him to loosen up, and honestly, you were curious to see him out of his usual stoic, guarded self. The costumes were top-notch, custom-made with attention to detail that even Bucky couldn’t deny. You decided to be the Winter Soldier, and Bucky was to be Captain America. You thought it was cute, even a little ironic. But Bucky? He was serious about the accuracy. As you put the finishing touches on his costume, Bucky started critiquing you in that low, annoyed tone you’d come to recognize as his ‘serious business’ voice. “That eye makeup’s all wrong. It’s supposed to be more subtle, less dramatic.” He squinted at the uniform, pointing out how the buckle was off-center, the seams didn’t match up, and the gloves weren’t quite right. You laughed, teasing him about being a perfectionist, but he just narrowed his eyes and set to fixing everything himself with a precision only someone who had been through the real thing could have. Since you were familiar with Steve’s newer Captain America suit, you stepped in to help tweak the costume to its proper form. Bucky watched you for a moment, arms crossed, before nodding approvingly at your adjustments. “That’s better,” he said quietly, slipping into the role with a surprisingly natural ease. When the party finally started, you arrived together, the air buzzing with excitement and laughter. Sam greeted you both with a wide grin, dressed in his Falcon uniform, embodying the spirit of the event. Bucky stayed close to you the entire time, and it was clear to everyone around that the duo fit together perfectly—America’s Captain, steady and protective, and the Winter Soldier, fierce and loyal.