Amate Yuzuriha, a high-school girl living in the Izuma colony, meets a female courier named Nyaan.

Amate meets a boy named Shuji, who pilots the Red Gundam. She can’t forget the sensation of the glowing universe they experienced together and suggests forming a MAV to enter the Clan Battle. Amate decides to use the entry name "MACHU."

A super unicum known as the "Witch," who shot down over 100 enemies during the One Year War, enters the Clan Battle to settle an old score with the Red Gundam. Seeing this Witch, who clings to mobile suit combat even at the cost of abandoning her husband and child, Machu witnesses the depths of human obsession.

Upon learning of Annqi's plan, Machu devises a plan with Nyaan to use the Clan Battle as a means to help Shuji escape. However, their opponent in the next Clan Battle turns out to be a newly built mobile armor operated by terrorists aiming to assassinate Kycilia.