Ginjou Kuugo is a Fullbringer who has come to Karakura Town to give Ichigo back his powers, in exchange for removing his hollow. His appearance begins the Lost Agent of the Shinigami arc. He surfaces when Ichigo Kurosaki managed to stop a mugger that had stolen a duffel bag containing all of Kuugo's belongings.
Lost Agent of the Shinigami Arc
Ginjou offered to take Ichigo out for ramen as thanks for helping him, but Ichigo refused and told him to keep this incident a secret as he did not want his father to find out that he had hit someone and get yelled at for doing so. When Ichigo left, Ginjou mused about Ichigo's wariness and pulled his own Substitutes badge from his bag to ensure its safety before looking back at Ichigo with a devious grin plastered on his face.
Ginjou later shows up at Ichigo's workplace, an jack-of-all-trades shop owned by Ikumi Unagiya, who is somewhat afraid of Ginjou at first, and offers Ichigo a bowl of ramen that he has brought with him.Ichigo kindly declines the offer and tells Lost Agent that he is in an eel shop, which agitates Ikumi greatly as they are no such thing. Ginjou then sits down and begins eating the ramen, which enrages Ichigo as it is not his "break room", which Ikumi denied it being Ichigo's either, and that he should go home.
After a long-winded argument about ramen and coincidences, Lost Agent finally explains the reason why he has come there and holds out a picture of Ichigo's father, Isshin, which heats up another argument and leads to Lost Agent cryptically hinting about many secrets Isshin is hiding that Ichigo wouldn't possibly know as he "isn't even supposed to know his family yet". It is revealed that Ginjou has recruited Yasutora Sado into his team of Fullbringers. At the moment, he is allowing his mates in helping to regain Ichigo's powers.
Ginjou is revealed the true villain of the Lost Agent Arc. After stealing Ichigo's fullbring powers to become even stronger, he battles the protagonists when his true shinigami powers come back. But during the confrontation betweem the two of them, Ginjou reveals an unexpected truth: the true enemy that Ichigo must fight is not the XCution... it's the Soul Society itself.
In the subsequent battle, Ichigo manages to kill Kugo. Soul Society retrives his body but the young Kurosaki requests to bring him back to Earth so that he could be propelly buried.
Kugo is an astonishing swordman. Hi fullbringer consists in a Saltire pendant that he can transform into a large claymore named Cross of Scaffold, a long and wide weapon. The sword's handle runs through its guard, continuing on through a hollow space at the base of its blade. This part of the handle allows Kūgo to attack opponents at closer ranges. On of the sword abilities consists in charging energy attacks that Kugo can throw at his enemies. At impact, these attacks can cause explosions strong enough to knock down buildings.
Kugo can enhance his Cross of Scaffold by fusing it with is Shinigami's Badge. He can also stole other people fullbring powers, upgrading his own. His complete Fullbring form take the appearence of an armor formed by plates that look like skeleton's bones.
Kūgo's theme song, as chosen by Tite Kubo, is "Last Man Standing" by Bon Jovi.