Don't give him that look, Ianto, you know exactly why they're confused.

"No," John says, "I'm sorry but I'm with TJ on this. I thought you were miniature home-world security -- you know, alien threats. So did you name an alien after a biblical threat or are you also The Slayer part time and the rift is a hell-mouth?"

This is something you should have mentioned, Ianto! Demons! Demons are absolutely worth mentioning! There is no way John can just let go of demonic things suddenly being part of your job!