Mirim was an ordinary, timid village girl who moved to the city to raise money and support her family. Lured by the promise of a fat paycheck, she agreed to become a test subject for Ymir's research into "the ultimate weapons and armor".
Her sword, shield and armor make use of the vibrating-crystal technology that Ymir developed; they are more than powerful enough to offset the fact that their wielder is completely unskilled in combat. However, the armor has one minor design flaw: the positioning of the vibrating crystals can be... distracting to the wearer.
