Dr. Song was such an odd mix. She appeared to love and actually said she trusted the Doctor, and yet she'd killed him. Or would. Even in the face of the young clerics dying - and although his dislike of her was strong he could see she regretted each of those deaths - she trusted the Doctor. He shouldn't have let her get to him, threatened her. Because when he did, although her face was tight with anger, her eyes were anguished again, and Father Octavian felt as though he had been unjust. Of course she wouldn't let the Doctor know what she was... it was in her own best interest not to.
And the Doctor led them through the maze, realising the Angels were all around them, doing ridiculous and undignified things like jumping into the air to escape. Using cover fire as a light source. Chatting with an Angel who had killed Cleric Bob as though there was nothing wrong (until you looked at his eyes, which were just as anguished as Dr. Song's). Being smug and flirting with the woman when they'd given him up for dead.
And then it was just the two of them. Father Octavian and the Doctor. And the Weeping Angel who was going to kill him, kill them both if he didn't sacrifice himself. But he'd seen enough of the Doctor by now to know that no matter what, the alien would not rest until he'd wiped each and every Angel off the face of this planet. He still did not understand how the Song woman would kill this man she purportedly loved, but it didn't matter. All that mattered was that the mission would be accomplished, the people of this planet safe.
And so he was content.
The three of them, the only three left, climbed wearily out of the wreckage of the Byzantium. Amy was complaining loudly about bruising her shins, and the Doctor was telling her she needn't keep her eyes shut, so he almost missed River surreptitiously wiping away a tear. He moved closer to her, keeping an eye on her even as he more or less dragged Amy along behind him. "Alright, Professor Song?" he asked in an undertone.
She nodded and glanced at him, and although her eyes were full of tears, her voice was steady and quiet. "He was a good man, wasn't he?" The Doctor didn't pretend he misunderstood. He nodded and she let out a sigh. There was a gust of wind as they broke out onto the surface, and her voice was so quiet that he almost didn't hear what she said next.
"Another one has gone to war because of me."