Misaya is described as "a perfect beauty". She is a young girl with red eyes and long black hair tied into a half up. She wears a white top with a black fur jacket along with navy short shorts and brown boots. She also wears a school uniform in a style like Ayaka's, as well as a V-shape red dress that reveals her Command Seals, located on the back of her neck.
During the events of 1991 Tokyo Holy Grail War, Misaya (as a child) used to wear prim and proper dresses similar to Rin Tohsaka. She also used to wear pure white nightgowns.
Misaya Reiroukan is a noblewoman; she is sadistic, proud, elegant, cruel, and calculative. Though not much is shown, a line said by her during the montage in Fate/Prototype was "I wanted to summon a Hero who was killed by a woman. That way he would know how scary a woman can be."
Despite what can be inferred by this, the Fate/Prototype Material book has a line from Lancer saying he likes her, as she reminds him of his teacher, Scáthach.
As a child, Misaya used to be a very kind and trusting individual who while innocent and naive, carried the traits of a ruler. She loved both her father and mother.
During the 1991 Tokyo Holy Grail War, she was particularly close to Caster (Paracelsus) whom she considered to be a friend. However, when Caster betrayed her father and killed him, Caster confronted Misaya and coldly told her that "Magi do not have friends in the truest sense of the word." The traumatic impact of Caster's words and the shock of his subsequent betrayal, as well as, her mother's death after the Grail War thus fueled Misaya's transformation into the cruel individual that she is today.
It is also implied that in the years after the 1991 Tokyo Holy Grail War, she may've forgotten what happened due to the shock.
Fate/Prototype: Fragments of Sky SilverEdit
In the 1991 Tokyo Holy Grail War, Misaya is shown as a younger child version of herself, She is not a master yet still being very young. Originally, Misaya is a somewhat normal little girl who is studying the basic of her family's magic under the tutelage of her father while attending school.
Before the Holy Grail War started, Misaya decided to stay with her father rather than go to their villa in Izu with her mother and staff.
On the seventh day of the Holy Grail War, Misaya helps out to make dinner under the instruction of Caster's Homunculi.
During the Battle of Tokyo Bay, Misaya is at home sleeping when Manaka Sajyou infiltrates her dream. Misaya later wakes up to discover her father bursting into the room. Suddenly, Misaya's father starts turning into an undead. Sputtering out words, Misaya's father tries to warn Misaya of Caster's betrayal and informs her of the uncurable curse that has been placed on her. Misaya's father additionally informs Misaya that she must seek out and obtain the Holy Grail as that may cure her condtion. Losing control, Misaya's father stabs her in the chest with an Azoth Sword and casts suppression magic into her curse.
On the morning of Day 11, Misaya wakes up to discover the mansion empty and her stab wound gone. Searching the mansion, Misaya discovers her father dead in the courtyard Shocked, Misaya grabs her father's hand and recalls the moment when her grandfather died. Suddenly, Caster appears behind her and confirms that he was the one who killed her father and placed the curse on her. Touching Misaya's cheeks, Caster whispers, "Magi, do not have friends in the truest sense of the word" before leaving to join Manaka.
Misaya is the version of Rin Tohsaka that was to be used in the original Fate/stay night novel which had been penned but was left uncompleted. In Prototype, information on her has been expanded on to show she has savage black dogs as her familiars along with her summoned Servant, Lancer. They worked together in tandem in order to hunt down another potential Master, Ayaka Sajyou, and kill her.
Much like Rin, she had lost her father in the War. However, she is cursed. The curse was cast by her father who had thrown everything away to attain the Grail, stating "Die if you do not become a Master and get the Grail". Towards the middle of the actual war, she would die due to this curse and her Servant, Lancer, would form a contract with Ayaka, who at that time had lost Saber to Berserker's Master, Sancraid Phahn.
However, it's said that the person who had really cursed her was not her father, but ■ ■. Her father had struggled to undo the curse, to no success, after which ■ ■ kills him. The curse covers her entire body, killing her. ■ ■ then transforms her into a "Fallen" (a shambling zombie).
Despite nothing being shown by the animated version beyond her created familiars and the capacity of sealing Gae Bolg, it's said in the Prototype material that Misaya has the abilities of rune magecraft, black magic and all sorts of summoning spells.
As a child, Misaya displayed tremendous natural talent with magecraft. She was capable of summoning and using animal familiars and was subsequently able to use her clairvoyance in conjunction with them to see through their eyes. She could also repair barriers.