Kiyal Bachika is the youngest of the three Black Siblings, a family of orphans who hunt beastmen. Her name is derived from the Japanese word yaruki, meaning willingness. She is a spirited and mischievous young girl with a distinctive fang that protrudes from the left side of her mouth.

During the battle against the Beastmen, Kiyal initially serves in the control room of the Super Galaxy Dai-Gurren alongside her sister Kiyoh. Seeking a more active role, she later becomes a frontline pilot, taking command of a customized Gunmen which she names the Kiyalunga. This machine has the unique ability to transform into a shield and a lance, which can then be wielded by her older brother Kittan in his own Gunmen, King Kittan, forming a combination known as King Kittan Deluxe.

Kiyal shares a close and protective bond with her siblings. She lives in the shadow of her boisterous brother Kittan and her older sisters, often acting as the energetic tag-along. Following the defeat of the Spiral King, she resides in Kamina City with her sister Kiyoh and her husband Dayakka. In this more peaceful era, she displays a childlike demeanor, such as when she playfully criticizes the actions of the provisional government.

When the Anti-Spiral activates its human extermination system, Kiyal is present at the hospital during the birth of her niece and is forced to evacuate. She witnesses the immense scale of the war against the Anti-Spirals and endures the emotional weight of seeing her brother Kittan sacrifice himself to break through the Death Spiral Machine. As a core member of Team Dai-Gurren, her latent fighting spirit connects to the team’s collective power. In the final confrontation against the Anti-Spiral, she, like the other members, harnesses her Spiral Power to manifest a colossal Space Gunmen, contributing to the formation of the Super Tengen Toppa Gurren Lagann and standing alongside her comrades in the battle to save the universe.