She was the root of all evil. But she was a darling to him. Despite being painfully aware of her manipulative nature, he held up their relationship; there was just no other way. He’d likely not survive not having her, such was his subversion.
She, of course, knew of the control she exerted over him; made the most of it, really.
Found this in my drafts on GMail. Prolly a story arc at some point, never developed it fully.