A/N: I have not read the books yet. My knowledge of the series is limited to that gleaned from the TV show and from various spoileriffic fanblogs. Because of said fanblogs, however, my fanfics typically combine both TV show and book references. Apologies for any inaccuracies!
It had always been innocent...until it wasn't. But it started out innocent enough. They were children, after all. "I'll be the stallion and you be the mare," Cersei had said...or was it the sow? In any case, Jaime had agreed readily. It had never occurred to him to object, to say that as the boy, he had to be the stallion. Which one mounted the other was immaterial—they were alike.
Their mother had thrown a fit, but at the time, they were mystified as to why. The understanding came years later, in the night, as they held each other—held each other as they had done since they were babies and likely also in the womb—and Jaime ran his hands over his sister's changing body. He could feel the newly formed curves of her hips, her budding breasts, and they stirred something strange within him.
They had compared each other's bodies early and often, in their rooms, at bathtime, watching the changes with a mixture of disgust, fascination, and heartbreak. They had been each other's mirrors for so long that any divergence in their paths was unwelcome. Would Jaime still be Cersei? Would Cersei still be Jaime? Cersei in particular hated the changes, hated how she got only useless mounds of breasts, while her brother was developing the hard muscles of a warrior. She didn't know how much of it, if any, was due to gender and how much was due to the swordsmanship training only he got to receive, but either way, it infuriated her. She grew more violent in their quarrels, more likely to slap him at the slightest provocation. Jaime didn't fully understand his sister's envy, but he never resented her rages. He saw them as the natural counterpart to his own newly discovered bloodthirstiness during swordplay—proof that they were still alike, and therefore comforting.
Cersei murmured incoherent words of pleasure as he pinched her firm nipple between his fingers. She shifted against his own rapidly hardening cock. Her brother's hands roamed over her without hesitation, exploring the body that had always belonged to him. One found its way in between her legs. It was wet there. On impulse he sniffed his fingers, then licked them. "Sweet sister," he whispered. The commonplace phrase, spoken between them, seemed to take on new meaning. Cersei turned over in his embrace to kiss him, to explore his body in turn. She grabbed his cock and squeezed, watching his face. Jaime closed his eyes for a moment. "Cersei," he gasped.
"Yes, sweet brother?" That beautiful fierce Cersei look.
"Oh, Cersei." He met his sister's eyes and saw his own soul there as she shifted again and guided his cock into her—it slipped out. They tried again. He thrusted into her hard—she cried out in pain and he stopped, kissed her again to make her forget the pain. Finally he laid down on his back and she lowered herself onto him. He fingered her clit as she rode him hard, her nails in his back, his golden lioness, her tawny gold mane falling down and brushing softly against his face. She rode him until they were both tired, and then they fell asleep in each other's arms as always. Only to wake up in the middle of the night, possessed by a nameless restlessness, a nameless excitement. This time he pulled her up onto her knees and did it to her the way they had seen as children, the way stallions and mares did it. Her moans grew louder with each thrust, feeling the power of it inside her, her twin brother's cock filling her. She wanted him inside her always, she had never felt so complete. He buried his face in her hair to breathe in her scent as her tight hot wetness devoured him.
That was the first time. It got better later on, as they grew more knowledgeable.
Jaime remembered this and other times during the long nights out in the field, in his encampment, as he rode in battle into the North. It was a way of staving off the loneliness. He remembered, and also dreamed of the future—dreams he never would have dared to have a mere few days ago. Cersei was queen, and queen alone. Ned Stark and the lot might mutter about legitimacy, but what was it his father had said? A lion did not concern himself with their opinions. No throne had ever been won by legitimacy—thrones were won by the persuasive power of money and force of arms, every child in the Realm knew that. Why shouldn't he marry her, proclaim what they'd always known openly? The Targaryens had always done it.
Waking up mornings in her chamber, luxuriating in the silk and velvet bedcovers she shared with no one, in the beautiful silence, no drunken lout snoring beside her, Cersei also remembered. She remembered what she'd said to Ned Stark, about how she'd supposedly "worshipped" dead Robert as a girl. Was it true? She'd lied for so long and so often that many times, when speaking to people other than Jaime, she could barely remember whether what she spoke was lies or truth. Certainly she'd dreamed of Robert as a girl, as she'd dreamed of Rhaegar. But in her dreams of Robert, she had only ever been able to imagine him seated beside her on the Iron Throne, proclaiming her queen above all of them, just as with Rhaegar, she'd forever pictured him flying with her on a dragon's back, safe high above the world. Whereas with Jaime—she trembled and closed her eyes, remembering the night before he'd joined the Kingsguard, the inn where they'd met in secret, her dressed as a servant—though Jaime had said, "you'll never make a convincing one, you carry yourself too much like a queen"—the scratchy hay-stuffed bed they'd lain down on, how she'd taken his body over and over, ecstatic in the knowledge that he was hers, hers alone now, hers alone forever. Years later she could not regret that night, but she looked with nothing but loathing now on the naïve teenage girl she'd once been. She'd been nothing but a fool, believing in fairy tales: the old story of the girl who becomes a princess by marrying a prince. And now she saw that same idiot light in Sansa's eyes. Sansa dreamed of and believed in fairy tales, as Cersei once had, but also as her father still did, with his ridiculous ideas of honor—and that was the difference between them. Sansa would stake her entire life on a fairy tale, because she had never known anything real. And that was the reason why the lion would always defeat the wolf.
