Well, 'gg' could stand for various things. If it's in the context of a bedtime story, perhaps it's a story that a particular person named 'GG' likes to tell at bedtime. It might also be a type of bedtime story that has a certain pattern or theme related to the 'gg' concept. For example, if 'gg' stands for 'gentle giants', it could be a story about kind - hearted, large creatures. Without more context, it's hard to say for sure.
I don't think it's a true story. Usually, when something is labeled as such, it's more in the realm of fiction, crafted to captivate and take us on an imaginative journey.
GG usually referred to a good game, but it could also be understood as an excellent game or a winning game. In novels, GG usually referred to a character who performed well in the game and won a game or battle. GG is usually used to describe a powerful and victorious game scene. It can also be used to describe a character's heroic behavior in the game.
I'm not sure specifically as there could be many novels with that title or concept. It might be about hopes and dreams for the future, with the'maybe someday' suggesting anticipation of things to come in the story.