What should my book be about

If 당신 want your book to be similar to the ones 당신 mentioned it would be 더 많이 within the action 또는 adventure genres. All good stories have romances in them. Not all, but a lot. I think 당신 should write whatever 당신 feel led closest too and see where it takes you. Who knows, maybe you'll start on a dramatic and action packed romance and it might lead 당신 into the characters becoming vampires. And that might only set off the path of starting a series 또는 trilogy. It all depends on what 당신 feel 당신 should write. It is your story and your imagination. Let it run free!
I hope I could be of some help. Good luck with your book!!!