Tavros has no idea what a vader or a mum could be. Or Germany for that matter. But he guesses there's a similar concept at work here, a creature of some sort that acts as guardian. And since Alex is using past tense, he figures the guy doesn't want to talk about it.

Time for a subject change!

"Yeah... I basically just got here. I-I don't really understand, what's going on, or why I'm a chosen whatever, or any of that stuff."