The High court of Yevon is now in session.Maester Kelk Ronso at the opening of Yuna's Trial
Kelk Ronso is the leader of the Ronso, and a maester of Yevon in Final Fantasy X. According to the Final Fantasy X Scenario Ultimania Kelk is the Minister of Civil Affairs within Yevon, which is in charge of the judiciary, treasury and general civil administration. Though he appears in only a handful of scenes, his actions greatly influence both Yuna and Kimahri.
Kelk is a tall elderly Ronso with white hair and beard. His horn is almost black. He is the only Ronso witnessed wearing Yevonite attire rather than typical tribal outfits of leather armor. He wears an orange Yevon attire with the elaborate front with the symbol of Yevon in the center that maesters wear.
Kelk is formal and mature. He has human-like speech and sophisticated mannerism, quite unlike the broken English spoken by most other Ronso. When Kelk sees that Yuna is willing to sacrifice herself for the good of Spira even after falling out with Yevon, he praises her determination. Unlike the other maesters who seem to use their positions of authority for personal gain or to spearhead personal ideals, Kelk is shocked when learning of the temple's corruption. Despite this, he comments that Grand Maester Yo Mika's wisdom is invaluable to the people of Spira.
According to Final Fantasy X Ultimania Omega, both Jyscal, the leader of the Guado, and Kelk, leader of the Ronso, became maesters of Yevon as part of Grand Maester Yo Mika's "sub-races appeasement policy." Kelk is in charge of administering Spira's judicial system and puts summoner Yuna and her guardians on trial for the murder of Maester Seymour. He is the only one of the maesters unaware that Seymour had killed his father, Jyscal, and learning it troubles him. Following Yuna's sentencing, Kelk has had enough with Yevon's hidden secrets and betrayals, and returns to Mt. Gagazet hoping to find honesty and order in his mountain home.
When Yuna and her guardians escape imprisonment and reach the Mountain Gate, Kelk denies them passage up the sacred mountain because of their interactions with the Al Bhed and Yevon. Upon realizing Yuna is willing to sacrifice herself for the good of Spira even after turning her back on Yevon, he praises her resolve, and lets them pass.
Shortly after, the now unsent Seymour advances the mountain intent on continuing his mission to become Sin. Kelk had promised Yuna and her guardians the Ronso would bar the path of any intruders wishing them harm. When Seymour is prevented passage, he slays every Ronso in his path, including Kelk.
Kelk is the only maester who is neither seen nor mentioned in Final Fantasy X-2.