In the novel's ending, the mystery is finally resolved. The identity of 'A' is revealed, and the girls are able to put an end to the constant torment they've been through. They also learn a great deal about themselves and their friendships along the way.
Spencer is also very popular. Her intelligence and competitiveness can be the center of many fanfictions. Writers can write about her academic struggles, her relationship with her family, and how she uses her smarts to try and figure out the identity of 'A'.
One idea could be exploring a different backstory for one of the main characters. For example, what if Aria had a secret relationship with someone before she moved back to Rosewood. This could add a whole new layer of mystery and drama to the story.
In the end of the Pretty Little Liar novel, the girls triumph over 'A'. The revelation of 'A's identity gives them a sense of relief and they can then focus on rebuilding their lives and mending their friendships.
Yes, it is. There are often real - life events or experiences that inspire the creation of such a story. It could be based on someone's real encounter with a liar or a series of lies that had a significant impact.
I'm not sure specifically as I haven't read it. But generally, it might be about a character who is a little liar, perhaps exploring the reasons behind their lying, the consequences it has on their life and the people around them.
Actually, 'The Little Liar' is purely fictional. The plot and characters are all crafted by the author's creativity rather than being inspired by real-life events or people.