The youngest of the players. She was involved on a hypnotism TV show, but after it was reported to be a scam by relentless reporters, she tried to commit suicide by walking out in front of a vehicle. She then had a change of mind at the last moment and wound up paralyzed instead of dead, so she is confined to a wheelchair. It’s because of her past that Rei is shy and tends to be nervous around others. She is harassed by Eiji at first, but when Yuu comes to her rescue, she is grateful and reveals the truth to him. Eiji overhears and reports it to the rest of the group who is shocked, but accepts it right away.
She is not immediately in the area when Yuu awakes in the hospital, be he does run across her broken wheelchair and savaged stuffed rabbit. Her cellphone is the device found displaying the cryptic message that "Rabbit Doubt" has started. Beside her wheelchair Hajime finds the words "Atonement for killing both legs", along with the catch phrase of the game "The liar must die." This leads Yuu to speculate at one point that they are being forced to play the game as punishment for some crime. She is the one that causes all the torments that are around in the gameRei's bar code is on her thigh.