"Someone who doesn't realize it's a Hellmouth?" Jo ventured a guess
She found what she wanted to wear and darted into the bathroom to change. She was glad to be invited along on a hunt. It showed a lot about how much Dean's attitude towards her had changed, that he was taking her along as a partner like this.
She was also happy about the date-like overtones to this outing, and she'd be damned if she wasn't going to at least look the part of normal girl for their first date.
She didn't take nearly as long in the bathroom as a normal girl, but long enough to do a little something with her hair. She stepped out of the bathroom and looked over at Dean with a smile.