This .. sang. An absolutely appropriate description for a book where music was so integral to the story.
A violin teacher who is trading the souls of her students to hell to free her own.
A starship captain who has fled an apocalypse with her family to run a doughnut shop on Earth.
A young trans girl violinist who needs a home and a teacher.
These three elements are thrown together and mixed to make this book. They shouldn't work (even individually) but they do. Much as there is no big action sequences in this (it didn't need them) its an unflinching book, not frightened to show the dark stuff as well.
This book had me hooked from the opening pages, I could barely put it down. Definitely one of the best things I have read this year so far. A strong recommend.