Sometimes things happen unexpectedly. The 14-year-old Hikari, a classmate of Ryouga Kamishiro, also has to realize this when she unexpectedly and unintentionally holds a Heart Piece in her hands as an invitation to the World Duel Carnival. Someone must have played a nasty joke on her! But Hikari accepts the challenge.
What does she have to lose?
But when her first opponent is the person she least expected, the shy, sickly girl wants to finally face all her fears.
But not only Hikari has to realize very soon that life often has surprising twists and turns.
The 17-year-old Ayami, whose mother disappeared five years ago, hopes to find answers by attending the World Duel Carnival. Together with her best friend Satsuki, she faces the challenges of the tournament and encounters unbelievable things.
And what is with the mysterious young woman named Ruri? Or the girl Kimiko, who seems to be there whenever a certain charming Pro Duelist shows up.