What kind of PJ's should I wear?

I was supposed to go shopping in the states with a girlfriend but she had to cancel and I was kind of disappointed. The new guy I'm dating offered to come with me and we're going to spend the weekend shopping (well I'm shopping, he'll probably just follow me around and hold my purse haha) What kind of PJ's should I wear at the hotel? We haven't had yet but I've wanted to for a long time and I think this will be the time that we do. Just wondering, what would a guy want to see a girl wearing to bed and lounging in the hotel room?