The Snow Queen Quest is unlocked by performing a number of actions after returning to St. Hermelin High School after the Mikage Hospital, but before leaving through the hole in the wall (which puts the player on the main, or SEBEC, quest). Once the route is unlocked, the player should acquire the Snow Queen Mask, which is then taken by Saeko Takami. Ms. Saeko is then possessed by a malevolent spirit inhabiting the Snow Queen mask, who plans on sacrificing her as a way to bring about the Eternal Night. The Snow Queen then proceeds to freeze over the school and, in order to preoccupy the party until the ritual is finished, raises three towers (Thanatos Tower, Hypnos Tower and Nemesis Tower) and appoints previous victims of the mask, Kumi Hirose, Michiko Matsudaira, and Yuriko Yamamoto, to gu