Kureha Tsubaki tends a hidden Yuri Flower with her girlfriend Sumika Izumino at Arashigaoka Academy, on a version of Earth where bears once turned on humans and years of mutual slaughter followed. A "Wall of Severance" now separates the two species, until the alarm sounds again and bears cross the barrier, forcing Kureha to question what a bear actually is. This manga adapts the original Yurikuma Arashi story.