Jack Harkness has given a low, appreciative whistle. The little childlike part of his mind that gets overly excited at something new is still active even after everything he's been through in this world, and he is looking at a real life Capital-D Dragon.

And she's talking to him.

Jack might as well be a kid in a candy store. He's only going to get to experience talking to a Dragon for the first time once. Better make it count. He hasn't even made a move for his sword, instead raising a hand in a wave.

"Hello? Uh, Captain Jack Harkness, and who are you?"