The Mirror
Watch out for spoilers!
The Mirror is able to copy people like a reflection in a mirror and (literally) become that person. It is also capable of becoming a mirror and reflecting objects. Mirror appears to be troublesome and mischievous, but it really is a frightened and lost spirit. Mirror is the most human of the cards, as its ability to duplicate an identical copy of its (usually human) target also allows it to speak and express emotions. Before its capture in Episode 25, Mirror injures Toya but later is seen crying in guilt about it. Right before returning to card form, Mirror (in her normal visible form) apologizes to Toya. Mirror seems to have a special affection and is very shy towards Toya.
Mirror is one of Sakura's most helpful cards, as Sakura can essentially clone herself in order to be in two places at once. Usually this is done in situations where Sakura must distract Toya in order to capture or transform cards; unfortunately, Toya sees through the magic right away. However Toya keeps this a secret, instead interacting with Mirror as if it were an individual person. Through these interactions, Mirror develops a fondness for Toya, though never reaching a point of confessing her feelings (if they are that deep).
Mirror's visible form resembles a beautiful light sea foam green-haired girl, draped in a long flowing hanfu holding a mirror in her hands. On some occasions, Mirror just appears as the mirror that she carries, useful for reflecting images and deflecting magical attacks.
After Episode 61, Mirror wears a green ribbon in her hair. It is both an early Christmas gift from Toya and a gift of thanks for protecting Sakura during times when he cannot (Toya knew she had long hair in her true form). Mirror is transformed before Episode 61. At the beginning of the episode, Sakura returned to her room and thanked Mirror for covering for her.
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