Kyou Misumi is a 17-year-old high school student in the same class as Kenji Kusanagi and Tsubaki Tamashiro. His reserved and mysterious personality, combined with his composed demeanor and good looks, makes him popular among female classmates. He pilots the Big Shooter for Build Base, a role he held longer than Tsubaki initially knew.

As members of Team Shiba, Kyou maintains a competitive rivalry with Kenji in Hyper Motor Bike racing. Their unresolved race to determine who would advance to a final competition is interrupted by a Haniwa Genjin attack, an event carrying emotional weight. Kyou consistently challenges Kenji, pushing him during races and battles.

Kyou guards a significant secret about his identity and connection to Jeeg's power throughout much of the series. His limited presence intensifies this mystery. Near the story's conclusion, his true nature is revealed: he is a Guardian Spirit originating from the ancient Yamatai Kingdom era. This supernatural origin recontextualizes his actions and motivations.

Beyond piloting, Kyou contributes to Kenji's development and helps resolve central plot enigmas once his true nature is uncovered. His existence as a mystical entity introduces additional power dynamics for Jeeg against the Haniwa Empire.

In the climax, Kyou transforms, merging with the Jeeg system to become the "God of Destruction." This self-sacrificial fusion aims to permanently defeat the Great Jama Kingdom. His integration into Jeeg's systems directly facilitates the final victory against Queen Himika and her forces.

Information regarding his background or development is limited to the 2007 anime series.