Simon Cozzato is surprised at the Primo's Guardians suddenly appearing, and shouts G's name in shock. G introduces everyone simply as Giotto's guardians and plans to leave with Cozzato to find Primo, leaving the other guardians to fight off the Simon Famiglia's attackers, as they do not want Demon Spade to figure out that the guardians are helping the Simon. Cozzato thanks them and the memory ends.
Back to the present, all of the conscious members of both the current Simon and Vongola Famiglias are shocked, except for Enma, who appears to be brooding over this. Demon Spade is outraged after realizing that Primo saw through his plan to turn the Simon and Vongola against each other. Adelheid Suzuki and Kaoru are shocked as they realize that Cozzato wasn't killed after all, and Reborn comments that the handed down history of the Simon appears to have been rewritten. Tsuna is thrilled to discover that Primo and Cozzato's friendship wasn't broken after all, and Demon Spade is furious that Primo tricked him and faked Cozzato's death. Then Reborn wonders, why haven't they heard about Cozzato after the battle ended because he should've lived long after the battle ended if he wasn't assassinated. Everyone is surprised once again, and Demon Spade comments that even he hasn't found any record of Cozzato after the battle. Everyone is silent for a moment. Then the silence is broken by Yamamoto's laughter, and comment that everything must be fine, then, if Cozzato had lived after all. Tsuna is taken aback by Yamamoto's cheeriness and Gokudera is irritated while Reborn just says that he is as simple as ever.
Suddenly, Adelheid and Kaoru cry out in pain, and the Vindice begin to take them away for losing their challenges. Tsuna and Yamamoto shout out Adelheid and Kaoru's names in shock and horror, and then Adelheid, crying, asks Tsuna for a favor: save Enma, because his heart is broken so badly that he doesn't even care that he's been lied to by Demon Spade anymore. The only one who can redeem him now is Tsuna because Enma believed in him up until the Inheritance Ceremony, and while Adelheid doesn't expect Tsuna to forgive her for everything the Simon have done, she says sorry before her mouth, along with the rest of her body, is chained up, and is taken away. Tsuna yells out Adelheid's name in grief as Kaoru groans in pain. Yamamoto shouts his name, and then Kaoru, as he is taken away, says that they should be friends from now on, if it's okay. Yamamoto says his name again, this time in grief and shock, and then yells it again after he's gone.
Tsuna and Gokudera bow their heads in grief as Yamamoto grits his teeth. Then Demon Spade begins to chuckle. He declares that people led astray by the past are just foolish children, and that while he was surprised by the differences between his and Primo's past, he would continue with his plan, because to him, the future was what mattered. Gokudera and Tsuna are angry at this, but before any of them can do anything, Yamamoto suggests that Tsuna take a little break, and declares that Demon, the ghost of the past that brought so much suffering to the Vongola and Simon, would be killed by him.
Tsuna is shocked at the revelation of Yamamoto's fury, and Demon laughs at this, claiming that Yamamoto is getting cocky and that someone like him couldn't possibly kill him (Demon). Mist rushes towards Yamamoto, and as Tsuna, alarmed, realizes that Demon Spade's body is blurring, Reborn revealing that it was an illusion. Yamamoto is unforgiving and motionless, and asks Demon if he was ready. Then he calls Ziro and Koziro's names as he unsheathes his swords and displays the twelfth form of his Shigure Soen Ryu Stance Twelve: Sadachi: Kirisame. Hibari watches sharply as Demon appears to be sliced into pieces from the many slashes. Tsuna and Gokudera express their surprise at this. Then Demon laughs, revealing his survival, and only Tsuna and Gokudera are surprised. He comments on how similar his style of naming attacks is to Yamamoto's and that such an attack could not kill him.
Yamamoto has already known this, and expresses that he learned it from Genkishi, and used it to "sniff Demon out." It turns out that Ziro, taking the form of his left blade, has an amazing sense of smell that instantly comprehends what's in the air he touches as Yamamoto's blade. This enables Yamamoto to figure out just where Demon is hiding. Demon is interested, but boasts that even if Yamamoto did find where he was hiding, he'd easily be able to avoid his blade. Yamamoto replies that that was why he used two swords, and that his twelfth style, combined with both blades, was the perfect counter against illusions. At the end, he figures out where Demon is hiding, and uses Koziro's blade to get ready for Shigure Soen Ryu's other 12th stance: Udachi: Kirisame.
*Note: Bold + Italicized = First Appearance