Erza Scarlet is the most kick-butt woman wizard in Fairy Tail, but in the past this indomitable fighter was... a slave? Now she finds out that her old companions have completed the evil device they were forced to build while held in slavery: the Tower of Heaven. What's more, their wicked master requires a sacrifice: Erza!

In a magical land where two moons shine, one student in the Tristein Academy of Magic, Louise, has acquired the nickname of "Zero." Why? Her "zero" talent! With a near perfect failure rate for her spells, the shock that Louise's summoning spell works equals the surprise of her new familiar, a human boy from Japan! The boy, Saito, must now serve Louise, but if he gets caught checking out the lovely ladies of Tristein Academy, he will feel his master's wrath!

Shinji is nearly defeated, but everyone is in for a surprise when Rider's true master is revealed! In the aftermath of Shinji's rage, Shiro learns about Saber's past and why her noble phantasm is what it is. But are things finally calming down? No one is prepared when Caster starts a new onslaught! Tosaka is determined to put an end to Caster's machinations, but it may prove harder than she ever imagined...