In Ben 10: A day with Gwen, your Grandpa Max is gone for the day. That means you get to spend some much-needed quality time with Gwen, who is your cousin. You'll watch some movies with her, play some games, and maybe even do some other stuff. Sure, she's your cousin, but the two of you seem to hit it off like no other girl you've ever met. You probably know where this is heading, but you'll never think of cousins the same way again after having a great evening with Gwen.