This is such a great characterization of Rufus; utterly hard and ambitious, but for a greater purpose, and truly believing in his cause. It's so appropriate that he would be attracted to equally opinionated and intelligent women -- and that he'd enjoy clashing with them somewhat. Bet the make-up sex was wild. ;) You've made his opposition to Dumbledore's methods so believable without making him a "bad guy." Fantastic.
"Which gutter did they sweep you from?" Rufus croaks. -- You tell 'em, Rufus.