I want to make a book about Blue Exorcist X Fairy Tail

It's about lucy how she gets heartbroken no knows because she hides very well with a great weapon a weapon only true friends and family can over look that
Would be a heartwarming broken smile only the her classmates see through it but only 2 people can fix it other than who saw through the whole and understood yes this a rilu book but I want to make a good tell if the idea is to depressing 😅