"Yes, Mistress, a soldier. I served with the humans back when I was one, in their revolutions..." John frowned at the thought and then looked back towards her, "I was killed in service, and then trained in hell for, as far as I'm concerned, the same job. To fight. When I was brought back by my witch, I devoted my life to service--it's all I'd ever known really. And that service was protecting her."
The thought of Cortana left him feeling a bit hollow inside, but he did his best to ignore it and then stared at her, "So yes, I'm a soldier."