John squinted, and looked away when she laughed. He knew she meant well, but it stung him still. "No, not me ma'am. Far from being a hero." He coughed, and wiped his eyes with the back of his hand "Jus' good at getting rid of vermin, thas' all."
He sighed dramatically. "Anyway, where were we?" He looked back up at her, voice a little overly bright, but he was getting there. "Yeah, Captain Jack bloody Harkness." He snorted. "'Course he didn't always go by that name. Anyway, we were partners," he winked at Lucy with a grin gradually seeping into his voice. "We umm.. were partnered in the Time Agency. He kept me in check, and I kept him alive. We were born in the 51st century, him in the Boeshane Peninsular, and me in some back water godsforsaken off-earth settlement. We umm.. travelled through time and space on our missions. These things come in awful handy," he tapped his wriststrap. "By the 51st century mankind has picked up some useful traits. Watch out for pheromones for a start." He tapped his nose, and grinned broadly. "Me, I'm a bit of a mongrel. There's quite a lot of pioneers in my time, frontier towns, yeah? And the locals were very friendly with my ancestors, let's put it that way." He winked.
That was a lot of information to give Lucy, but he was feeling generous, and hopefully it'd give her a little more trust about him.