If I were to make another book after the one I'm currently working on. I have two other Ideas.
Idea 1: Fifth Harmony are high schoolers who have not once interacted with one another but, they go on this trip to the woods, they wonder off looking around and notice that they had gotten lost. The woods start being weird and a women their guardian comes and reveals they are witches apart of a prophecy made 100 years back by witches who were being hunted. They are also told that they can either save the world or destroy it depending on if they can work together or not.
Idea 2: Lauren is a demon haunting this asylum where she had died there a long time ago. Present day Ally, Camila, Dinah, and Normani are all planning on going there and exploring after reading an article about Lauren and what happened to her and how she got there but the girls backed out leaving Camila alone. Camila explores, learns about Lauren.