Ame was princess and priestess of the fallen nation Ise, destroyed by shadow creatures called Shinobi. Her mother perished to these beings, fueling Ame's drive to find the Holy Weapon Giga Road, believed capable of annihilating the Shinobi. She ventured forth with companions: the elderly swordsman Sanda, her loyal retainer fulfilling a vow to Ame's late mother to protect her, and four girls named Hana, Yuzu, Rin, and Eri.

On her quest, Ame rescued Suou, the last surviving warrior of the Shinobi-fighting Yagyuu lineage, from near death. He joined her mission. During their journey, Ame fell in love with Suou. Her determination to wield the Giga Road was driven by revenge against the Shinobi, a motive others questioned, debating whether it stemmed from care for humanity or personal vengeance.

Ame's leadership faced trial when Sanda sacrificed himself to hold back Shinobi, enabling her to reach the Giga Road. The final confrontation exposed Tsukiyomi, her former tutor and an Ise scholar, as the architect of the Shinobi attacks, seeking their power for himself. Despite Tsukiyomi's betrayal and manipulation, Ame activated the Giga Road alongside Suou.

In the climactic battle, Ame made an anguished cry to Suou, declaring her love, apologizing, and expressing gratitude: "Suou I love you." After defeating the Shinobi threat, she vanished, seemingly merged with the sky. Her sacrifice permanently separated her from Suou, cementing them as star-crossed lovers.