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After Gaia's defeat, it and Doll were sent underground with Doll's memory of the events erased. She was eventually unearthed and discovered by Naua as an infant with pink hair and was adopted as Mexiah Furan, who became Chiaia's older sister. As Mexiah, she is the martial arts instructor at Holy Land Academy who, unlike her serious sister, is shockingly affectionate toward Kenshi.
Also not only is she a Sacred Mechamaster, she is also a Sacred Mechaguardian. Doll has little regard for the importance of life, shown when she laughs while trying to kill Aura during an early encounter. Despite this, she has an attraction to Kenshi that she believes is a remnant of when Mexiah's personality was dominant. In the last episode, Doll realizes she loves Kenshi as much as her other half Mexiah and she tries to prevent Lord Babalun from harming him.
Thanks in part to her actions Kenshi manages to disable Gaia and free her from it and Babalun. Once free she again assumes the form of Mexiah and she and her sister Chiaia are reunited.