Kyo Sogoru

The protagonist of this work. A 16-year-old high school freshman. Height: 176 cm. Weight: 65 kg. Class: D. Attendance number: 8. A typical hot-blooded character but also intelligent and knowledgeable, often solving test problems perfectly, which makes him popular among the girls. He is running around trying to gather members to revive the nearly disbanded swimming club. His catchphrase is "There's no way!"

After meeting Shizuno, he awakens as a Celebrant. From then on, he fights as the Gunner (pilot) of Zegapain Altair, gradually coming to learn the truth about this world. At one point, he falls into despair upon realizing the world he believed to be real is nothing more than data, but he later comes to understand that even as a Phantom, he is still alive, and resolves to fight the Gards-orm to protect the Maihama Server. His part in the medley relay is freestyle (crawl).

In a past battle with the Gards-orm, he once "died." "He before death" was calm, collected, and highly sensitive. He actually sat next to Shizuno in elementary school.

The current him is a being restored from the remnants of Phantom Buffer Data, and he has mostly lost the memories before he "died," but he gradually regains them during battles with the Gards-orm. His personality is straightforward and rough, different from before. He is also in a mutual love relationship with Ryoko (as he was before becoming a Phantom).

The past Kyo was the one who issued warnings like "Be careful not to get involved with Misaki Shizuno," intended as a message allowing the future Kyo to act on his own will without being tied to past actions.

In the final battle, he uses the Resurrection System in G-Fetus to become the only one to materialize. After defeating Abyss, he aims to complete the Resurrection System in the real world's Earth. Upon materialization, he regains not only all lost memories but also his lost former personality (which may be related to Gards-orm's technology). He even succeeds in integrating his personality based on the current Kyo.

At the 10th anniversary event "10th Anniversary Zegapain SBG Summer Beginning @Maihama Server," it was revealed that his birthday is July 16, 2006.

In the movie "ADP," which depicts before he "died," he is already awakened as a Celebrant from the beginning of the story. He exhibits memory gaps, especially concerning his family's last moments, which he cannot remember.