As someone who doesn't know Torchwood, she's just going to have to take Ianto's word for it when he says it like that, but from the looks and the verbiage, she can tell the conversation is at an end.

Speaking of those diagrams, she finds it odd that John's letting Ianto keep them, but she's not the Colonel and the entire place doesn't seem all that regulated by military personnel, anyway. Since they're roommates, TJ has a feeling that John has explaining to do no matter what, so when the question is posed, she doesn't see the harm in answering for the acronym.

"The SGC is Stargate Command. I was assigned there through the Air Force as a medic," she answers easily. "I planned on going to medical school before, well. Everything."

Icarus. Destiny. This place.