After she had carelessly let a highly unpleasant being inside at the last party, which resulted in Rush being attacked and injured, the TARDIS is now particularly diligent about examining the intentions of her would-be guests. Which is also why she isn't opening the door until Ianto or the Doctor are there to appraise them as well (besides those she already knows and likes, they receive an unlocked door). So it is all the more shocking when an unknown entity simply appears inside, breaching all her shields and convoluted dimensions like they were nothing, like not even Gabriel can. She jolts and ripples in alarm, dimensional properties and the flow of Time within her tensing around the intruder, without displacing a single atom of the tangible reality her guests are experiencing.

Most of her vast focus turns towards the entity with apprehension, and the fact that she isn't sensing any immediate ill intent goes some ways towards easing her alarm. The intrusion hadn't been violent or forceful either, somehow the creature had managed to match the subtle frequencies of her private contained reality with ease, existing in tune with her. And what is it, anyway? On the heels of anxiety follows curiosity and she reaches out gently, offering an inquisitive greeting. In the back of the diner, her humanoid form turns towards the manifestation and watches it intently, even though the action isn't a conscious one.