Disclaimer: I do not own A Song of Ice and Fire.
Sandor is no Florian and Sansa Stark is certainly no Jonquil and yet, he can't help but want to save the girl as he watches them beat her. Instead, he stand there, stands there in his white cloak and just watches. Watches like he watched his brother once beat his sister. No, he is no Florian, even if a part of him wants to be.
That white cloak had made him proud. Sandor had taken the best of care of it after they draped it 'round his shoulders. It was spotless, the hem never muddy. When he takes it off after the little bird's beating, Sandor notices a few threads loose. It gets worse. His cloak becomes grimy, stained with booze and the hem finally dirty with the filth of the streets of King's Landing. His king laughs and tells him he is finally looking like a proper dog again.
Sandor can't understand why he seeks out the little bird. He has long ago decided she is not for him to save, for him to have. She is not his sister. His sister had been plain and serious. He could count on his hands the number of times she had ever smiled. He can barely remember those smiles. He can never forget the bruises on her face, the bloody lip, or the empty look in her brown eyes. The little bird looks at him with those same eyes, but she is not his sister. His sister took his beatings, never left his bedside after the fire, and tried to get him to smile and laugh again until the day his brother killed her. So no, Sansa Stark with her dreams and songs is not his sister.
After the fire, he had forgotten what fear felt like. He knew the taste of it in others, could see it in someone's eyes. He enjoyed seeing the fear reflected there before he put his sword through them. Sandor could never remember faces, but he remembers eyes. He killed a girl once with the bluest eyes he had ever seen. He sees her when he forces the little bird to look at him. Sees them when he hears the other knights speaking of her moon blood. Sees them when the mob almost claims her. Sansa Stark has clawed her way into his very soul and the thought terrifies him, even more than the sight of flames growing closer to his face.
He realizes it when the city burns. The wine does nothing to erase the taste of ash and fear from his tongue, but it helps him understand. Sansa Stark is him. The little boy that once dreamed of being a knight, of protecting the weak, that begged his sister for songs, and loved nothing than wanting to find his own Jonquil. She is his innocence and his salvation wrapped up in flames and eyes the color of the sky.
He waits in her room smelling of fire, wine, and death. The city burns around her and he wants nothing more than her. To mold her very essence into him and repair his broken soul. Only the little bird can save him with her pretty songs. He wants, he wants, he wants. He wants so much he hurts.
Sandor doesn't think as he throws her on the bed and hold his knife to her throat. "Sing." It is a demand and him begging all at once. When she sings, it doesn't save him. He took the song. He hurt the little bird. Sandor didn't save Jonquil, he has destroyed her. When he leaves, he leaves behind his white cloak.