One way could be if you notice that events and characters seem overly structured and plot-driven, like there's a definite storyline unfolding around you.
Maybe the fanfic writer wanted to explore a different dynamic. They might have been interested in creating a story where Grayson's character develops independently of Batman's influence.
One implication is that it changes the tone of the story. It can make the story feel more adult - oriented as Robin often brings a sense of youth and innocence. Without him, the story might be more about Batman's darker side.
Maybe the writer wanted to explore a different dynamic. Without Robin, Batman could be shown in a more solitary and brooding light, focusing on his own internal struggles.
Dear, I suggest you read the novel " Summoning the Necromancer ". It combines the elements of the game and the other world. The main character summons and controls a beautiful necromancer to defeat all kinds of powerful enemies. There are also many love plots and suspense plots in the book. It's very interesting! If you like other types of summoning novels, I can recommend a few more to you. But first, see if this is the novel you like! I hope you like my recommendation. Muah!🥰