Shirou Emiya (衛宮士郎, Emiya Shirō?) is the parallel version of the Shirou from Illya's world.
Profile
Background
Shirou's background in comparison to his counterpart is unknown. He shows no reaction to Illya's presence, instead having Miyu Edelfelt as his younger sister. Through some unknown means, she was born as the Holy Grail and sought out by the Ainsworth family. Learning magecraft unlike his counterpart, Shirou fought to remove Miyu from the grasp of the Julian Ainsworth and allow her to escape to the other world. He eventually became captured and used as a means of keeping Miyu in check once she returned.
Personality
Shirou deeply cares for Miyu and her safety, willingly fighting the Ainsworths entirely for her sake. Although her sacrifice is intended to save the world, he rejects Julian's notion of needing to sacrifice one to save all and decides to accept the "evil" that comes with fighting against him. He greatly belittles himself in his inability to have truly saved her, calling himself the "worst of the worst."
Appearance
Much like his counterpart, Shirou dresses in a white and blue sleeved shirt and slim blue jeans, albeit both of which are in ragged condition due to his imprisonment. The most notable difference lies in a small streak of white within his otherwise auburn hair as well as several tanned streaks of skin throughout his body, the change of which most likely came about due to the extensive use of projection magecraft within his own timeline.
Role
Shirou is first encountered upon Illya, Tanaka, and Gilgamesh entering the Ainsworth estate to rescue Miyu. As Tanaka notices that someone has been imprisoned, they first believe it to be Miyu until hearing his voice. Upon him questioning how they know Miyu, he is overjoyed to the point of tears that she has made friends. Introducing himself as her older brother, Gilgamesh is excited that he is still being kept alive, although in a bad state, somehow having knowledge of his existence. He disparages himself for not being able to allow Miyu to escape the "chains of fate" after she has once again been brought back into the hands of the Ainsworths, begging them to save her.
Illya cheers him up by telling him that she will do her all to save her friend, causing him to once again weep as he claims that half of his wish has already come true thanks to her. He tells them to worry about Miyu instead of him, and they have no capability to open the magical lock of his prison before Angelica attacks them. Worried that she has returned, he tells them to run because she is dangerous. As Illya questions Angelica about Miyu's whereabouts, he tells her that she is at the top of the tallest tower, causing Angelica to use a spell to cause him great pain. Julian later threatens Miyu to take out any punishment that he cannot inflict on her body on her brother, causing her to become obedient for his ritual.
As part of their plan on their second assault of the estate to save both the captured Illya and Miyu, Kuro, Bazett, and Gilgamesh plan to rescue him to keep him from being used against Miyu. Gilgamesh also has some sort of motive in meeting him at least once, so he frees Shirou and tells him of the events until then. Once Julian uses the mysterious cube object to conjure a large number of Heroic Spirits, Shirou arrives as the rest of the combatants are overwhelmed and Julian is attempting to lure Miyu back to him by working at her conscience over her friends being in danger. Illya stops her by telling her nothing good would come of it, and Shirou agrees with her as he arrives.
He tells Miyu that she will no longer have to listen to Julian again, thanking all of her friends for fighting for her sake. He tells them to leave the rest to him to accomplish his duty as Miyu's older brother, crushing a number of the Heroic Spirits with Nine Lives. He tells Julian that he will accept "all the evil that comes with stopping him" if he is willing to sacrifice one person for the greater good. He asks Julian if he as enough resolve as a "hero of justice", and blocks a volley of arrows with Rho Aias. The members of Illya's group recognize him as Shirou, confused by his appearance. He projects Ig-Alima to act as a ramp to the formation where Julian resides, reuniting with Miyu on his way up. He apologizes for not being able to protect her, but states that he will end it all.
Encountering Angelica in Gilgamesh Install on the top, Shirou challenges her and try to invoke Unlimited Blade Works, but his body failed him. After Angelica cornered him, Kuro comes to his support and together they defeat Angelica. But on the way to Julian, Sakura Matou of Miyu's world in install form attacked him. Defeated, Beatrice Flowerchild toss him from Ig-Alima where Rin Tohsaka saved him.
Abilities
Shirou using Nine Lives
Shirou uses Projection with great efficiency. He is able to run through a field of Heroic Spirits that leaves the members of Illya's group easily pushed back, attacking and defending as he moves. He is able to project a Divine Construct, Ig-Alima, for which even Gilgamesh praises him even if it is a knockoff of the real weapon.
His sword skills are also worth noting, as he seems to employ a fighting style similar to that of Archer, a suicidal technique aimed primarily at combating physically superior opponents by reading several steps ahead of the situation, purposely leaving fatal openings to be exploited, and then countering the enemy as they try to exploit those openings.
Presumably, this iteration of Shirou is also capable of evoking Unlimited Blade Works in it's entirety.
References