The Orphan "Koji"

Her real name was not revealed. She called herself, "The Orphan" because she is one. She wants to find her own birthday. She died due to poison and she's the one who told Kujo and Victorique about the bomb that was located at the train's rail.

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In the series, she holds a Memento Box which was stolen by "The Scarecrow" and was given back by the "The Knight." In the end, the box was handed down to Lesglant Gideon and was later revealed that the memento Box was actually Jupiter Roger's.