Mary Sera

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Profile
Japanese name:	???
Age:	Looks approximately middle school aged according to Conan
Gender:	Female (assumed by Conan)
Relatives:	Masumi Sera (Sister)
Statistics
First appearance:	Manga: File 875
Appearances:	Unknown child Appearances

An unknown child of middle-school age who appears to be a girl with light hair was shown hiding in Masumi Sera's room. The child's eyes have a remarkable resemblance to those of Shuichi Akai and Masumi Sera.

Appearance

The child appears to be a female of middle school age (12-15) with light colored, curly, neck length hair. The child has eyes similar to those of Masumi Sera and Shuichi Akai. In her appearance in File 877, she was shown wearing a high-neck pleated top, hoodie jacket, and hat.

Plot overview

The Red Woman Murder Case (875)

The child on Sera's phone.

Masumi asks Conan to find her cellphone by calling it with his. He does so and Conan notices the call background screen is a child who looks like Masumi with eye bags similar to those of the Akai family members. Masumi never mentioned having a younger siblings earlier, so Conan suspects Masumi was intentionally trying to show him the child for some reason.

Romance Novelist Murder Case (876-878)

When Ran, Sonoko, and Conan visit Masumi's apartment, the child is shown opening Masumi's door as Conan, Sera, Sonoko, and Ran rush to investigate a crime. It is implied she was hiding in Masumi's bedroom while the other three were in the dining area because Masumi asks Conan not to enter her bedroom. The child later goes downstairs to the scene of the crime where she is seen by Conan. After the case is solved, the child is shown examining Conan's bug along with Masumi. She says that it is still early to trust him, and asks Masumi to introduce her as "her little sister from outside the territory", should Conan question her in the future.

Identity

The child's relationship to Masumi Sera is unknown. Sera testifies that she has two older brothers: Shuichi Akai and an unknown middle brother living in Japan. She says her father is dead, and her mother lives overseas in America. Masumi says she doesn't have any more relatives close enough to depend on. She is currently being financially supported by a friend of her father's. If Masumi has told the truth, that leaves relatively few options for the child's identity assuming the child is related by blood somehow to Masumi.

Fan speculation

Akai family mother

One possibility is that she is the mother of Masumi Sera and Shuichi Akai, shrunk by a drug. There are currently five known members of the Akai/Sera family: a deceased father, a mother, a son who resembles the father, and Masumi Sera and Shuichi Akai, who presumably resemble the mother. Her eyes and features are similar to those of Masumi Sera and Shuichi Akai, and so she presumably looks like the mother of the family. Sera seems to recognize Conan Edogawa to be Shinichi Kudo despite him having such a young appearance, and if she does indeed recognize him she is not surprised by his appearance, which could imply that she is aware of age regression and the drugs which cause it; and perhaps even looking into it because her mother was affected by such a regression.

Middle brother

Along the same lines as the mother theory, another option for the child's identity is the middle brother of the Akai family shrunken by some drug such as APTX 4869. The child's appearance as a girl may be misleading similar to how Masumi is mistaken for a man, something the child in trying to take advantage of in order to conceal his true identity. Although the eyes are similar to Masumi's and Shuuichi's, the blond colored curly hair sets the child apart from the other two in appearance.