Amu Hinamori, a reserved girl plagued by rumors of her aloof nature, yearns to reveal her true self to others. One day, she awakens to discover three vibrant and intricately adorned eggs in her bed, each containing a Guardian Character representing her inner desires. With the guidance of these characters—Ran, Miki, and Su—Amu gains the courage to express her authentic identity. However, her newfound abilities draw the attention of the Seiyo Elementary Guardians, a group with their own Guardian Characters, who enlist her as their 'Joker' to track down corrupted X Eggs. As Amu delves deeper into this mission, she unravels the mysteries surrounding her Guardian Characters, the X Eggs, and the enigmatic organization pulling the strings behind the scenes.