Shadows of th Past is a Yu-Gi-Oh! GX fanfiction that talks about Reika Tsumura's past. It is not associated with the official Yu-Gi-Oh! GX series owned by Kazuki Takahash. It was published on Fanfiction.net on March 18, 2015.
Reika has had tough past. What happened exactly before she transfered to Duel Academy?