He hadn't expected this—though, he supposed, he should have.
Branson had noticed her beauty the first time he was introduced to the girls, to the family he liked far more than he had anticipated. He was, however, more preoccupied—as any man would be—by that of Mary, legendary Lady Mary Crawley. But at that point, they were still just his employers, just silly girls he would drive around to their silly engagements.
But then Sybil intrigued him. There was a quiet passion in her voice not possessed by the others. And then, of course, the revelation of her support for women's rights, of her political mind. He had known that she was the kind one and that she was helping Gwen, but this surprised him. He hadn't imagined that any upper class lady would have such controversial opinions—didn't they leave that to their husbands? He grinned to himself at this, possibilities racing through his mind, glad his passengers couldn't see.
He admired her as well, as he began to pay more attention to her. She was somehow soft-spoken and outspoken all at once. She didn't pretend to be submissive or demure; she accepted his pamphlets gladly and questioned him with intelligence. Then there was the frock—the frock that was obviously about more than just getting her way with a dress; again she displayed her quiet way of asserting herself, still with the class that befitted her rank but with the spunk that it so often lacked. He wrote off the helpless grin that took over his face when he saw her glowing as she showed it off as pride—telling himself that the sudden quickening of his heart had nothing to do with her ankles (or eyes, or smile) but rather hope for progression, for women.
This continued as she nearly walked to the end of the earth for Gwen, who spoke so highly of her. To hear her talk, one would think Lady Sybil was really Queen Sybil. They crossed paths when she came in, a satisfied look on her face despite the mud covering her entire being (it wasn't clear which of these made his heart skip a beat).
A slight protectiveness had also emerged from his respect. He hadn't quite been able to concentrate when he took her to see the speakers—he had been to so many before that he could tell when things were getting out of control. Yet there was the pride again—for the exhilarated fascination on her face as she listened, for the reluctance to leave. He guided her out, one hand around her back, fighting several internal battles at once: should he let her stay? Was it right to have brought her? How much pressure was proper to put on her arm? When did he have to let go?
All this was true, but he still had not expected this, the enormity of what he suddenly felt. He wasn't sure when it had happened, when the dam had broken—somewhere between the moment she turned her back on him and the moment Mr. Crawley had lifted his hand to see blood. He had never been happier to see Matthew since they met; he needed someone, something solid, for he was in free fall and was unable to regain control at the worst possible time. He was helpless—helpless against her will, helpless against the riot, helpless against his heart. He didn't like the look of this and said so; knowing that his words would do nothing. Then he saw her go down and there was the blood and he knew that if the worst happened he would deserve anything he got, that he would never be able to face himself again. He lifted her without hesitation and carried her, knowing that he would carry her all the way back to Downton if it would have helped. He drove them back to the house faster than he'd ever gone, reeling the whole time, feeling as if the world had turned upside down.
And now he stood in front of Downton with Lady Mary, relieved and ashamed, trying to make her see that he would never endanger Sybil and that she mattered more—so much more—than his job, than any political dream, than anything. He didn't know that he and this woman were suddenly kindred spirits, that she too had experienced this sudden onslaught of emotions for someone whose back had also recently been turned on her. He was not a lunatic, but suddenly, for a moment, he felt like one.