A lot of things depend on if someone would buy a book or not. The characters, the plot, the genre, the theme, the storyline, everything varies. People like certain things, and if they don't like certain things they don't buy them. For example, animals. People who are fans of animal books are attracted towards Erin Hunter's popular series Survivors and Warrior Cats, people who like horror go for Stephen King or R.L. Stein. It all varies.
If you truly enjoy your book, go for it! Someone will enjoy it and be attracted to it, I'm sure. If you do decide to publish your book, I wish you the best of luck!