Board Thread:Theories and Speculation/@comment-36300243-20180723092044/@comment-1458758-20180910053140

Kashin Koji might be Jiraiya. I say this simply on the basis that I spent literal years telling people Tobi is not Obito only for that very frickin' thing to happen and annoy the bejebus out of me. That aside, I will play devil's advocate and say why Kashin Koji might be Jiraiya, even in the face of opposing evidence.

Q. Jiraiya seemingly died in Amegakure. A. What I think the author of this thread was trying to articulate, is that Jiraiya's body was never actually retrieved by either side in the war and Kabuto's explanation leaves it open to say that he wasn't "in the pure world". So if the writer wants, they can say Jiraiya didn't actually die die after his fight with Pain.

Q. Even if Jiraiya survived, his body was super messed up. A. Kara has shown the ability to make highly advanced nanomachines capable of giving a person abilities akin to Jugo, restoring Jiraiya's wind pipe, vocal cords and arm with no apparent mechanical parts probably isn't beyond the abilities of these machines given Kawaki can generate massive amounts of hardened flesh to battle with. An expenditure they're probably willing to make for a member of the Inner group as opposed to an Outer like Ao, who is basically a test bed for Ninja Tech.

Q. Jiraiya and Kashin Koji look rather different. A. Consider the resources at Kara's disposal. They clearly have access to high end medical technology and even with ability even half as good as Orochimaru, it wouldn't be unreasonable to assume that if they're going to go through the trouble of dragging Jiraiya back from the dead, they may just want him closer to his prime, so while Koji bears little similarity to older Jiraiya with his wart and the red marks, younger Jiraiya had relatively plain features that could be hidden by Koji's mask and the rest is just apparel and grooming.

Q. Personality wise, Jiraiya and Koji are not at all similar. This is true, but then, Obito's younger self was not at all like him when playing the role of 'Madara'. Jigen says that Koji is loyal to the mission, but that he has a curiosity to him that makes him kind of capricious. Starting with the fact that we don't even know what Kara's mission statement is, it's not impossible for Jiraiya to have memory loss, be under the affects of a genjutsu or have his mind straight up altered by Jigen, leaving the more whimsical aspects of Koji as what we know of Jiraiya, a curiosity and interest in things like Konoha and Boruto, the son of his student.

This all being said, I think Koji might be one of Minato's teammates from his genin days, like that black haired kid with the top knot.