Kinon Bachika is the second oldest of the Black Siblings, a group of four siblings who are first encountered by Team Gurren in their travels. As a member of this family, she is a younger sister to Kittan and an older sister to both Kiyoh and Kiyal. Among her siblings, she is distinguished as the calmest and perhaps the most intelligent, often serving as a steady presence in contrast to their more boisterous nature.

Initially, Kinon is introduced as part of a misguided attack on the Gunmen Gurren, a misunderstanding that is quickly resolved. After this event, she and her sisters develop an immediate infatuation with Kamina and Simon. Rather than joining her siblings on the front lines of battle, Kinon finds her niche in a support role. Following the capture of the massive Gunmen Dai-Gunzan, she takes up a position within its control tower, where she works as a radar and systems monitor. Her analytical skills and strategic mind become valuable assets to the team during this period, and she continues in this capacity through the war against the Spiral King, Lordgenome.

Following the seven-year time skip, Kinon has matured into a young woman and taken on a more politically significant role. She becomes a primary supporter and close aide to Rossiu Adai, the new commander-in-chief of Kamina City. Her loyalty to Rossiu is profound, and it is implied that she harbors strong romantic feelings for him. Her dedication is tested severely when Rossiu, believing Simon to be a threat to humanity's survival, sentences him to death. In a display of her steely resolve, Kinon volunteers to pilot the Gunmen Gurren, which is to be fused with Simon's Lagann. She rigs the cockpit with explosives, claiming she will detonate them to kill Simon if he attempts to escape, thereby showing her willingness to sacrifice herself to support Rossiu's difficult decision. Her actions are not born of malice but from her understanding of Rossiu's torment; she witnessed how much it pained him to betray his former comrade and recognized that he acted not for personal gain but out of perceived necessity.

Kinon's character reaches a critical point of development when she helps save Rossiu from himself. Overwhelmed by guilt for his actions, Rossiu flees to his desolate home village with the intention of committing suicide. Kinon discovers his farewell message and immediately joins Simon in the Gurren Lagann to stop him. She is instrumental in this rescue, as Simon physically confronts Rossiu while Kinon provides the emotional anchor, ultimately tearfully reuniting with him and reaffirming her support. This act demonstrates her growth from a simple supporter to someone who takes decisive action to protect the person she believes in. In the final events of the series, Kinon stays behind on Earth to assist Rossiu in the administration and reconstruction of Kamina City while the rest of Team Dai-Gurren departs to face the Anti-Spiral threat.

In terms of abilities, Kinon is not primarily a front-line fighter. Her primary contribution is her technical and analytical aptitude, best utilized in monitoring and strategic coordination from a command center. She is, however, capable of piloting a Gunmen when the situation demands it, having piloted the mecha Gurren on at least one occasion during the conflict with the Anti-Spirals.