Grimmjow never fell asleep holding her, but somehow wound up doing so unconciously. Whenever he woke up, she would always be curled up in his arms, her soft skin teasingly brushing his stomach. His arm laid against hers, her soft hand within his. She seemed so small and innocent against his rugged form, but he knew she wasn't. She hadn't been since she met him.
He always awoke before her, too. Grimmjow hated feeling inferior, and having her awaken before him would make that sentiment arise. Without even knowing, Grimmjow had made her aware of this.
There was an extensive list of other things she could not do. She couldn't converse with anyone besides him, she couldn't leave his room without his permission, and she couldn't get dressed unless he told her so. But just because she couldn't do these things didn't mean she wouldn't.
Perhaps that was why Grimmjow was so enthralled with this woman, though he would never admit it. Without even the slightest warning, she would disobey him, and he would punish her. Harshly. Maybe she enjoyed his abuse, which would explain why her behavior always warranted it. Or maybe she just did it for the attention. But Grimmjow didn't really care why she did it. He would always find a reason to smack her around.
She actually didn't know why she always gave Grimmjow a reason to hurt her. She might have actually liked the way he would roughly smack her face, then grab it and kiss her senseless before hitting it again. But that probably wasn't why. She only knew that she liked to be dominated, and Grimmjow would certainly fulfill that desire.
She found it difficult to exist around him, and even more so when he wasn't there. For some reason, she had become addicted to his harsh words and treatment, and she knew she wouldn't grow out of it.