Knighting Shining Whatever
She didn't want it to happen.
Yes, sure, she was still human, and yes, she lusted after him, and yes, he would be a catch; but she didn't want anything else, just to feel his arms around her as he filled her up.
She had more important things to worry about than love. And love had never taken her anywhere, but to doom, despair and treason. She had betrayed every one she had ever loved, and they had betrayed her as well.
But those feelings wouldn't go away, and even after she set him free, Gwaine stayed. He smiled at her, his easy and charming smile. He told her things - sometimes rash, sometimes sweet, but always true. He knew what she was, who she had become, what she had done, but he didn't hate her for it. He didn't even pity her - she would have killed him if he did. He seemed to understand.
And when she raged, and shrieked, and lost control in her grief and anger, he would hold her, allowing her to cry until she calmed down. He would sooth her, and rock her to sleep, and if she woke up later, burning with lust and demanded him to take her, he would happily agree.
She didn't need to be saved, what she needed was revenge - and he became a bitter one, always coming to her and making her feel things she didn't want to. She wanted to shun him away forever, but she could never deny him when he came, his rough hands and soft voice, his concerned eyes and easy smile, walking in with a juggle of wine.
She didn't want a Knighting Shining Whatever, but she found one anyway.