For the first time in his life, he was completely happy. Life teached him to be selfish and completely self-reliant, to thrust nothing but his own senses and cunningness, and no one but himself. He had to fend off his own way through life, wasn't proud of what he had become, but becoming a thief was at the time his best alternative. Through his entire life no one cared about him in the slightest, always surrounded by people who would use him as easily as discard him. At least there was a positive side about this: he grew up to be tough, not a pampered boy, with a thick hide, and nothing about life surprised him.
But every armor has its chink, and he found his. He'd never know someone as her before. Completely naive, yet highly intelligent. Tender, and surprisingly strong. Someone who didn't judge him, an innocent, raw, untarnished soul. He had no defense against this. She could see good in him, peering through the layers he had so carefully built over the years, and piercing his heart with her child-like, beautiful green eyes. She trusted him, perhaps because she didn't know better, but that trust, her delight over the simplest things, her bravery, not to mention the fact that she stood for him, not fled, when things got rough, just because they were casual companions, the way she cared, every single thing about her screamed past his mind, directly into his soul. That was it, she reminded him he had one, carefully stowed away so it wouldn't suffer, wouldn't cry, wouldn't feel the void, the loneliness of a life without honor, truth, and love.
The whole card castle crumpled, trashing before her tiny feet. He would show her the wonders of the world and protect her from its evils, no matter what the cost. He thought it could very well be his ruin, taking in an unknown girl with freakingly long, magic hair, the sweetest of smiles, no clue about the world and no shoes either. He would do anything, go anywhere to protect her world, for she had saved him without knowing it. He never thought that love such as this could exist, and thus finally found a reason to live, a road worth traveling, a place worthy of being called home, and they all had her name.
The real him showed up in force and, by seeing life again through her amazed eyes, he was being transformed, little by little, into the person he would have been in another, kinder life. The only thing that remained from Flynn Rider was his tough hide, his keen senses, his enhanced awareness of evil and its many disguises, as they were forged through scars and bruises, and so were burned into his very skin. But that was good, and necessary, as she had none of it. He stood amazed that she liked his real name, liked him as he really was, liked his real, astonished faces as much as she had been impervious to his fake smiles and smolders. She began to love him, and he couldn't believe it. Things as pure and beautiful didn't exist, and if they did, didn't happen to him. Yet there she was, looking at him with eyes of hope, and love, and it was real, and so he'd be her guide, her shield, her friend and lover, and whatever it was she needed. He'd give his life for her, as her love and happiness were his new and only dream .
For the first time in his life, he was completely happy, as the time had come to choose between him and her, between his life and her freedom, and he had embraced death without a hint of doubt, without lingering for a second, and had freed her from eternal slavery. He was proud of himself, his life, at last, having had purpose, even at its end, and he had enough strength left to confess to her, and she felt the same. And so, as life escaped his body, as light abandoned his eyes, as everything began to turn cold, and silent, he had only one regret, and it was not having been strong enough, cunning enough, to live for her instead, and to know that she would cry and suffer, and would be left alone.
And then a miracle happened. There was light, yellow, and red, warm and bright, and it called him, and had her voice. Suddenly he was there again, life coming back to him, and as he breathed again it smelled sweetly of her, so that when he finally opened his eyes, all was full of her, teary eyed, astonished, looking at him with such love and tenderness, and there was neither pain nor fear as she embraced him with all her strength, and they kissed, and she was everything.