In another world, an ever-growing Sea of Snow has engulfed the planet surface. The people struggle to survive living around the routes of a massive Orbital Tree, whose branches spread into the Celestial Membrane high above the ground. Change comes to this dying world after Kaina, a boy from the Celestial Membrane, encounters a girl from the surface called Ririha.

• Yoshimasa Hosoya
• Rie Takahashi
• Ayumu Murase
• Maaya Sakamoto
• Katsuyuki Konishi
• Tomokazu Sugita
• Nobuyuki Hiyama
• Kenyu Horiuchi