Amused, Trey watches Vanessa dig into her food. His grin fades, however, when she asks for more specifics regarding the Yeerks. He brings his glass to his lips, taking a long sip of his drink, stalling for time, though he isn't exactly sure why.
"It's very possible," Trey murmurs at last, replacing his now half empty glass. A small belch escapes him, but he seems to not notice. "The Yeerks were, I mean are, parasites. They enter in through your ear canal and wrap themselves around your brain. The result is total control over motor functions. You are still aware, but you can't do anything with your body."
Trey pauses again, a look of discomfort on his face. "They are normally blind, deaf and basically helpless. So they sought out hosts to give them control over their world. With a little help from the Andalites they were able to travel the galaxy and gather more hosts. Unfortunately, the Andalites decided they made a mistake and were...are...hell-bent on destroying the Yeerks. In my time -" Trey cuts off, glancing down at the table. "Well, it doesn't really matter what happened in my time. Point is that the Yeerks exist, and so do a whole lot of other aliens."
Now it is Trey's turn to look at Vanessa with curiosity. "So, on your Earth there are no Yeerks or...anything? In the year 2010? Humanity is still self-contained?"