In A.S. 106, five years after the Vanadis Incident that led to the condemnation of all Gundams, these cursed mobile suits now roam the surface of Earth. The story follows Vilda Mirren, a researcher who once studied GUND medical technology at the Vanadis Institute, and her young assistant Kiyu Lavot. Together, they travel across the Earth aboard a massive transport trailer carrying the Gundam Lfrith Jiu, a mobile suit equipped with a gigantic arm unit called the Tiger Hand that can also function as a backpack-mounted booster. Their mission is to put an end to the curse created by the ideals of GUND technology.

Kiyu Lavot serves as the pilot of the Gundam Lfrith Jiu. His chest houses a light described as an immature bloom, and his journey with Vilda represents a story where a curse stimulates the heart. The boy has a past connection to the Rocking Horse Orphanage, a facility where children were trained as Gundam pilots after receiving GUND artificial hearts implanted by a researcher named Shijima Joma. These artificial hearts provide resistance to the deadly data storms that normally plague Gundam pilots, as the Permet within the artificial organ acts as auxiliary memory containing feedback information. Shijima Joma, who now operates under the alias Craig Ion as a district politician with ties to the Ral Craig Group, survived the Vanadis Incident by escaping in a mass-produced test model Lfrith and continues to seek the advancement of GUND technology through his experiments on children.

Kiyu faces a rival in Yoshika High Gear, another child from the Rocking Horse Orphanage who pilots the Gundam Lfrith Anocta. Yoshika harbors an inferiority complex toward Kiyu, who always placed first in their training while Yoshika came in second. Acting under orders from Bas Issa, the woman who managed the orphanage and trained the children as pilots, Yoshika is sent to eliminate Vilda when she refuses Shijima's request to cooperate with his plans. In a confrontation between the two Gundams, Kiyu shoots down Yoshika, who subsequently suffers cardiac arrest and requires life support.

The narrative unfolds on Earth during the gap between the events of the Mobile Suit Gundam: The Witch from Mercury PROLOGUE and the main television series. The manga explores the aftermath of the Vanadis Institutes destruction and the continued persecution of those associated with GUND technology, who have been labeled witches. The series incorporates elements of the larger conflict between Spacians and Earthians that defines the Ad Stella timeline, while focusing on the personal journey of two individuals seeking to reclaim a technology branded as cursed from its darker military applications.