you are an ordinary boy at school, you go to the library to read a book as usual when choosing a book you accidentally find an old book tied with a black string, You decided to take the strange old book home

when you open the book the book immediately emits a very dazzling purple light and an explosion of smoke fills the room making you unable to see , when the fog starts to clear up a little, you see a little girl? But having wings on her waist?