Create a 8 sentence story outline for a book about a romance during the end of the world.
The story begins with the protagonist, a young woman named Ava, learning of a impending global catastrophe that will bring an end to the world as she knows it.
    As she struggles to come to terms with the news, Ava meets a charming man named Jack who has a similarly adventurous spirit.
    Despite the chaos and uncertainty of the end of the world, Ava and Jack quickly fall in love and decide to make the most of their time together.
    They embark on a journey to see the world and experience everything it has to offer before it's too late.
    Along the way, they face numerous challenges and obstacles, but their love for each other helps them overcome each one.
    As the end of the world draws near, Ava and Jack find themselves in a race against time to fulfill their bucket list and make memories that will last a lifetime.
    In the final days, they come to realize that their love is stronger than the end of the world and that they will face the end together.
    The story ends on a bittersweet note as Ava and Jack watch the world come to an end, hand in hand and surrounded by the memories they have made together.
List few of items from their bucket list and change a plot, that one of those items accidentally saves a world