"The Doctor?" she repeated curiously, but didn't comment on it. After all, she ran around calling herself Shadowcat half the time. "Nice to meet you, I'm Kitty," she introduced herself, offering her hand in greeting.
No sooner did she do so, when one of her 'friends' returned, waving a gun. "Ha! Not so tough with your ninja moves now, are you, bitch?" he taunted, aiming the weapon at the two of them.
Kitty acted quickly, linking her arm with the friendlier of the two strangers and making the both of them intangible, so that when the man fired, the bullets passed harmlessly through them, lodging themselves in the concrete wall behind Kitty and the Doctor.
Once she heard the distinctive click-click-click of someone attempting to fire an unloaded weapon, she let go. "I'll explain that in a second, assuming you don't run away screaming," she told the Doctor, before turning away to deal with the returning criminal.
[ooc: If any of this (ie, her grabbing/phasing him) is un-cool with you, just let me know and I'll change it.]