Time Slip Ichimannen: Prime Rose

A colossal space fortress called Death Mask breaks apart above Earth, sending fragments toward Kujukuri and Dallas. When the pieces strike, both regions vanish from the present and are displaced 10,000 years into a harsh future.

Gai Tanbara is sent after the impossible phenomenon and reaches a future Kujukuri reduced to desert and ruins. There he rescues Emiya Tachi, only to be captured and thrown into a labor camp controlled by forces connected to Death Mask.

Emiya carries a personal reason to fight the regime, and Gai soon learns that the disaster was no accident. Together they are drawn into a struggle against an oppressive power whose manipulation of time has transformed entire cities and the lives within them.