Author Note:
First off: Firefly belongs to Joss Whedon, Star Wars belongs to George Lucas. I'm not making any money from this, just for fun, yadda yadda yadda.
Second: Blue Sun Down was written by Darth Marrs and I strongly recommend that you read it before reading this. The story id is 3917281
Third: This is my first piece published in a public forum, so while I do welcome constructive criticism please be gentle...
Lastly: Enjoy (or lie)

"Well doesn't this just damn it all", he thought as pain blossomed in his chest. She flowed around him like a river around a stone, lightsaber flashing as it intercepted the other blaster bolts aimed at her lover but the damage had been done. He'd always figured it would end like this; it's what happened to men like him. But somehow he'd begun to hope that things might turn out different for him now that he actually had a good reason to stay alive for a good long while.
He forced his eyes open so he could see that reason again before he died. She stood between him and a whole gorram mess of ugly bad guys, the DL-44 that he'd named "Chloe" in one hand and her lightsaber in the other. Her clothes were torn and burned in several places from close calls with blaster bolts and in any other circumstance he'd have thought she looked damn sexy. Unfortunately the bad guys weren't gonna stop shooting so he could ogle his pretty angel.
He already knew he wasn't gonna make it back to the ship and if she kept tryin' to protect him then she wouldn't make it back either
He wanted to tell her to run, to leave him and get back to the others but before he could even say it she told him to "hush now sweetheart" before turning and placing a blaster bolt between the eyes of a particularly big and ugly lizard. Trany-shans he thought they were called. Stupid name.
Almost before the alien hit the ground the woman before him spun her lightsaber in a blindingly fast pattern that appeared as a blue wall which the pirate's blaster bolts bounced harmlessly off. Well, almost harmlessly. One of the red energy bolts ricocheted into the stomach of another pirate. The dozen or so remaining pirates took that as a sign to retreat and try a new plan. Taking advantage of the respite she knelt down beside him, her hands gently probing around the smoking hole in his chest. "You listen to me now little one, you leave Chloe and a grenade with me and get back to the ship, no sense both of us dying on this gorram dustba-argh!" She'd push down a little roughly on the wound, "them blasters burns don't half tickle." he muttered through clenched teeth.
"Toughen up you big girl, won't be much longer now."
"Yeah I know that, just wouldn't mind a little piece and quiet before the end rather than all this racket."
"I wouldn't worry about that," she replied as her lightsaber hummed back to life. "There'll be not a sound but for the Serenity in the air when you fall asleep."
He had to laugh at that, or tried to, but the burn in his chest stretched painfully and the laugh became a pained wheeze. He laid his head back and closed his eyes, listening to the crack of her lightsaber intercepting blaster bolts and the cries of the pirates who effectively shot themselves. He heard a dull roar beginning to fill his ears. "This must be it," he thought. A thought that was confirmed when the world became noticeably darker even through his closed eyelids.
The roar deepened before being punctuated with a bright flash of light and a high pitched whine. "What the..." he thought as his eyes snapped open. Above him, the familiar silhouette of a ship hovered, its turbo lasers vaporising huge chunks of dirt, foliage and pirate while their return fire pattered ineffectually against the hull.
It didn't take long before the remaining pirates had either fled or died, and after a few moments the freighter settled on its four spindly landing struts and the cargo hatch dropped open.
The first person out wore a long brown coat and carried an old officers pistol. The captains' eyes, long since used to the horrors of war, hardened when he saw the still smoking wound. "Wuh de tyen, ah! Doc! Get him to the infirmary quick." As the rest of his crew carefully moved the gravely injured man into the ship, the captain moved to stand beside her. "What happened mei mei?"
She didn't reply, just stared vacantly out at the impromptu battlefield. "C'mon little one," he gently urged her, "he needs you."
"He's still waiting. Waiting till it's safe..." She paused as if listening to something, "it's not safe yet."
Before the captain had time to be confused he caught a flicker of movement at the edge of his vision. Even before his hand touched his pistol she'd fired her blaster, the last pirate fell with a desperate gurgle, clutching at the charred remains of his throat.
"Should've waited longer," she whispered, so quietly that the captain almost didn't hear. Then she turned and ran into the ship. The captain followed right behind, activating the ramp controls as he jabbed the intercomm, "take us outta the world. Don't matter where yet, just break atmo as quick as you can."
She practically flew from the cargo bay to the ship's small infirmary where her brother worked to save the life of her lover. In all their time together he'd never said that he loved her. She knew he did, with all his heart and soul he did. But because he knew her heart still belonged to another he never said a word.
Now tears ran freely down her face while she stood just inside the door. Her eyes seeking her brothers, wishing for him to deny the truth she knew was coming. And for the first time she could remember, he couldn't meet her gaze. The tiniest shake of his head told her enough. A strangled sob escaped her throat as she realised he could work no miracles here, that the man who wanted little more than to make her happy was dying and there was nothing to be done about it.
Her brother gave a dying man one final injection to dull his pain, then came over to wrapped his baby sister in a tight hug. "I'm so sorry mei mei," he whispered, "even a full bacta dunk couldn't save him now."
"No..." she pleaded, tears spilling from her eyes. "There must be something we can do?" He squeezed her slender frame tighter for a second before releasing her. "All you can do is be there for him mei mei, he only has a few minutes left."
She nearly collapsed to the ground when her brother left, closing the door behind him. Somehow she found the strength to hold on just a little longer, he deserved that much. She walked slowly over to his bedside, her hand grasping his as she stroked his stubbled cheek. Slowly she leaned down until her lips just barely brushed his, tears and saliva mingling in one tender kiss. She carefully moved onto the bed, wrapping herself around him as much as possible without causing him any more pain.
"Thank you so much," she sobbed. "Thank you for loving me even when I thought I didn't want you to."
"You were right you know," he whispered. "Not a sound but for Serenity in the air. My Serenity and my River."
"Don't leave me," she begged, "please don't leave me Jayne. I love you."
"And I love you," he gasped as the life sign monitor dropped sharply, "my beautiful... River..." she felt his last breath shudder its way out of his destroyed lungs. At the same time the monitors began emitting a constant tone but River didn't register the sound. The only thought she had was that the man she had realised she loved too late was dead.