Quite entertaining
The time traveler really reminded me of "Invader Zim" both the show and the character. It was really on the loading screen where he had those spider limbs pop out. And like that show, this also had a good amount of humor. In fact, I think this is going to work out better as a comedy series than an action one as there was little action in this. While it could have used some more action, still very well done. I especially like how silly the girl is when she talks about God and stuff.
There's a perfectly logical explanation for her to be in that situation and it's at least scientific. The animation was flawless all around. This is the kind of cartoon that really wants you to know what happens next in the story. I have no idea why Brian went back in time or why he captured those two people. The idea of him being human was also quite original.