Mido Masatake was an Avatar-obsessed man who murdered people he found unsuitable to be their avatar, and would in turn take on their roles.
Mido had short black hair and black eyes. He wore rectangle glasses and was only ever seen wearing a gray lab coat. Prior to his death, Mido always bore an emotionless look on his face.
Mido had a strong passion for avatars, and worshiped them with utmost loyalty. Makishima found him interesting in that 'he could become anyone', though this seemed to be because he himself was 'no one', and thus he could pretend to be anyone with very little flaw.
Despite his cruel actions towards former avatar owners, Mido often displayed a lack of sympathy and emotion, and only began to express intense fear shortly before he was killed.
At some point, Mido was approached by Makishima, and offered help in fulfilling his dreams.
His first act was to kill Tokito Yuichi, in what was reported as an accident. His avatar, Rainy Blue, was then used by Mido in what remained as a flawless act. A couple of months later, he would brutally murder Hayama Kiminiko, and steal his avatar, Talistman, as well.
His second-known crime would then be investigated by the MWPSB, who, being suspicious of Talisman's continous appearances despite his owner's death, decide to follow him into CommuField, where Tsunemori Akane is contacted by an old friend, Sugawara Shoko, aka Spooky Boogie.
When a gathering planned by Spooky Boogie is infultrated by the police, Mido - as Talisman - accuses Spooky Boogie of siding with them. Although she denies and exits CommuField (due to strange threats), Mido appears right behind Shoko and strangles her. He later brings her body before Makishima, and soon, cuts her up.
Immediately after, does Mido also take on the guise of Spooky Boogie, thus playing as three different avatars at the same time, but with very little flaw.
However, things begin to go down hill for Mido when Enforcer, Kogami Shinya, begins to piece together all the evidence and manages to identify him. After a chase with the police and the loss of his arm, Mido arrives in his room where he is warmly greeted by his beloved avatars.
At the same time, Choe Gu-sung hacks into the avatars and enables Makishima to 'bid farewell' to Mido, who begins to panic. When the police barge in, Kagari is the one to shoot him, thus ending his life.
- According to the MWPSB database, he is 27 years old and works at a virtual sports management company.