Gunner is a young shinigami, who wanders around soul society as a bounty hunter, who takes jobs as they come and go. He has revealed that he somehow has a connection to Akira. He is known in certain parts of Soul Society because of his ability to complete his bounty hunting tasks quickly and perfectly. He is the leader of Sizaeon Clan and is well known for his great leadership and skills as the heir to the Sizaeon Clan. He is only known to have lost once and it was to Zancrow who at the time was thinking of joining the Sizaeon Clan.