The Wolf Girl and the Black Prince is one of my highest ranked shoujo mangas and I think if you're accounting the length of the movie and all the major details, the movie corresponded with the manga pretty well. I do wish it wasn't a movie in a way, since a drama would be able to develop but this movie was overall pleasing to watch. It depicted the relationship between the fake lovers and the relationship Erika has with the other people in her life. The rollercoaster of emotions did remind me of when I first read the manga which I have to applaud the directors for on that part. Even if you didn't read the manga (which is amazing btw), this is a good movie to watch if you're into the high school romance love genre.