Voice Range: Mid Level
Voice Example: https://www.youtube.com/watch?v=60CMajiKjoI (1:52-3:46)

Mash is a girl summoned from a parallel world. A member of the Organization for the Preservation of Human Order, Finis Chaldea, Mash is a being known as a demi-Servant: a successful fusion of a human body with a Heroic Spirit. Her Servant Class is Shielder. Her role is to jump to the point in spacetime of a problem in human history and resolve it, using the technology known as Rayshift.

Her hairstyle covering one eye is a key part of her fashion style, she also has a cute face, forthright personality, and honest, trusting character. Mash has learned about concepts like good and evil, and the purpose and significance of human life over the journey toward restoring her humanity.

In combat, she is excellent on defense and agile, using an immense shield much larger than she is. She also has strikes and throws using her shield, as well as techniques like kicks that launch her entire body from her shield.

In this title, an error of unknown origins during Rayshifting brings her to an unintended destination, into a nest of mysterious creatures in a world she knows nothing about.

Mash is a mysterious, kind-hearted girl. She refers to Ritsuka Fujimaru as her senior even before Ritsuka becomes her Master, feeling that something about them is especially easy to relate to. However, that smile belies a deep sorrow and resolve that has accepted her fate as a person with a set life-span since day one. As she has spent nearly all of her life in an isolation chamber within Chaldea, she is somewhat naïve and lacking in worldly experience. Despite this, she knows about a wide variety of subjects due to her education via Sheba, and she is especially knowledgeable about historical figures. Mash was initially designed to have no personality whatsoever in order to facilitate the Demi-Servant creation process, but Roman encouraged her to begin expressing her own opinions, allowing her to begin forming a sense of self.

Mash often fears that her Demi-Servant state makes her inferior to true Servants, and until she learned how to use her Noble Phantasm she thought herself to be all but useless to Ritsuka. Even before her Demi-Servant abilities manifested, she was devoted to the cause of Chaldea and sought to assist it however she can; when she is unable to participate in battle, she keeps a close eye on Ritsuka as a navigator. She does her best to hide her fear when in battle, and prioritizes keeping Ritsuka safe above all else. It has been hinted that she possess romantic and sexual feelings for Ritsuka as she is often seen blushing when compared as a couple with them. However, her naivety means that she does not yet realize what those feelings are.

Mash is a big fan of detective stories, especially Sherlock Holmes.