When R was younger, she did some pretend play (making believe to talk on the telephone, for instance), which at the time I thought was charming and creative: but compared to her elaborate fantasy life now, it was small potatoes. She now spends many of her waking hours inhabiting other worlds via her imagination. She especially likes imitating books and TV shows she's seen, where she is usually the heroic main character and I am one (or all) of the supporting characters. Favorites include Dora or Diego from Dora the Explorer, Cubbi from Gummi Bears, Frances the Badger, and Tintin.
Mostly, though, it's totally charming. I love it best when she is immersed in her fantasy play, quietly talking to herself as she acts out the different scenarios (like in the picture above): there is something so pure and beautiful about it.