This is not a new feature in iOS 14. You can follow along with Siri.
What you need to know
Ask Siri to tell you a bedtime story.
Siri will tell you the story of Goldilocks and the Three Bears with interactivity.
This works on HomePod, too.
We've all asked Siri some ... interesting ... questions, no doubt. We're always looking for a good Easter egg (Open the pod bay doors, Knock Knock, What does the fox say, etc.), and we recently discovered that, not only will Siri tell you a story, but it's an interactive one, too. It works with any Siri-enable device, including HomePod.
Siri's been telling stories for a long time. Previously, Siri told a story of a "young agent by the name of Siri" in a "virtually galaxy far, far away," but recent changes have switched the story to that of Goldilocks and the Three Bears. Not only does Siri tell you this story, but you get to choose which bear you want to be and what you want to do when certain parts of the story come up (will you scare Goldilocks, invite her to stay, or call her parents).
This choose-your-own-adventure story isn't new in iOS 14. In fact, it's definitely been around since May and possibly longer. It's just one of those fun little Easter eggs we only discovered by chance.
If you want to hear Siri's original virtual galaxy far, far away story, say, "Tell me another story." It'll take a few tries (it took me 6 tries) before Siri will tell the story, but it'll happen if you're patient.