She and Hephaestion were both already dead by the time Iskandar died. That is why the descriptions left behind about Iskandar don’t match the appearance of the Servant Iskandar at all. Not only that, but for the sake of protecting Iskandar from various forms of curses and magecraft, she developed numerous counter-intelligence schemes. Since giving her a name would weaken the spells redirecting curses from him to her she rejected each time. Not accepting these near inhumane circumstances, Iskandar attempted numerous times to give her a proper name and identity, all of which she vehemently refused due to her loyalty to him and her desire to continue serving him as his 'Shadow'. Combined with spreading rumors of Iskandar's appearance as based on her own, so distinctly different from his, she was the ideal vessel to receive any curses directed towards Iskandar. She was taught from a young age by Olympias, to act as a mage, body-double and confidant to Iskandar, and also acted for her brother at times. Because she had no name, she was able to magically impersonate Iskandar and draw in all kinds of curses. She was not just a magus, but Iskandar's 'Magical Shadow', as it may be hard to imagine her as a body double for a man like Iskandar who was over two meters tall. The former became the real Hephaestion, and the latter, her. She required a confidant for her son who would protect and never betray the King of Conquerors, and a mage who would defend the king from any oncoming curse.

Her birth was orchestrated by Olympias, Iskandar's mother. She was the younger twin sister of the real Hephaestion, one of the generals serving under Alexander the Great. From her summoning as a Faker-class Servant, the Class Name can be said to be the first name she ever received, so she has a preference for it. Never named at birth, the Servant lacks a proper True Name as a Heroic Spirit, but she is referred to as 'Iskandar's Shadow,' 'Hephaestion,' and 'Faker' depending on circumstances.

Lord el-melloi ii pixiv