As Katsura and Kyubei fight for the title of the best transgendered, Shinpachi leaves to find that the Shinsengumi members also suffered a sudden change in their selves; Sougo is the leader from the Shinsengumi and orders him and Hijikata, Yamazaki to attack the Yorozuya. As the three leave, Hijikata knocks out Yamazaki, as he was faking his change. He and Shinpachi learn that an invasion of parasite aliens is responsible for change to their friends and proceed to destroy them. However, they find problems in the outcome, and both Hijikata and and Shinpachi are knocked out in the process, with Gintoki being actually the only person without a parasite.
Shinpachi proceeds to throw Katsura Zurako into the ocean and makes him realise that his and Kyuubei’s characters have become further overlapped, so they decide to settle it once and for all. It’s now that Shinpachi’s partner over at the Shinsengumi arrives. He first suspects that it could be Sougo from how he had a bazooka fired at him, and while it is the Vice-Commander, it actually turns out to be “Jimmy” Yamazaki, who also happens to have an anpan addiction now. If this complete transformation wasn’t enough, Hijikata has undergone one as well, lowering his mayonnaise intake and becoming the Shinsengumi’s errand boy, Toshi. However, if Hijikata isn’t in command of the Shinsengumi it only means that Sougo has taken up the leadership, becoming Kaiser Okita de Sade Sougo III and turning it into an empire, planning to take over the Kabukichou before any further expansion. And it’s for this that he had Shinpachi join, as by holding him hostage he will be able to easily deal with it’s current general, Gintoki. But as Hijikata and Jimmy Yamazaki lead him away, Hijikata reveals in the same predicament as Shinpachi. Having escaped, Hijikata explains to Shinpachi that becoming “Toshi” was his attempt to laugh off everything that had happened, and they start to talk about why this only seemed to happen to them, with Shinpachi feeling that it was him falling behind as a straight man. As just like him, Hijikata was also a straight man but instead tried to play the funny man sometimes, and in the end they accept this and decide to go back to their old jobs, wishing each other the best of luck as straight men.
However just as they do this a news report about a parasitic wart that changes the host into what they aspire to be and gives them the impression that two years have passed. And with the cure being to simply smack them with a fan, and so with this the two straight men are back in business. As the head out though, Kagura arrives in tears and embraces Shinpachi, telling him that the Yorozuya without him is like him without glasses, and unable to even move in this sort of situation, Hijikata brings down his fan at her. However, this blow was blocked by none other than the Kaiser Okita de Sade Sougo III, who reveals that the acts he committed in order to expand the Shinsengumi were so that Hijikata wouldn’t have to dirty his hands. So Shinpachi goes to deliver the finishing blow, but Otae arrives with her newborn child and stops him. Revealing that the father is none other than Hijikata, and that she’s left Kondo to be with him. Soon after this though, Kondo also arrives and reveals that he has his own “child” before attempting to make off with the one Otae brought along, threatening to jump off the edge. Because of this, Hijikata begs him to spare his son and not long after this, Zurako arrives with one as well in order to convince him not to jump, and if this wasn’t enough, Kyuubei arrives with one as well and attempts to make off with them all. So with all of this, Shinpachi takes them all out in one decisive blow and finds that Hijikata was also infected by a wart. Having done this, he now resolves to do his best and get even better, however Gintoki arrives and reveals that Shinpachi was actually a wart all along. He then removes his wig and questions why he was the only one not infected as he uses the Final Getsuga Tenshou.
- Shimura Shinpachi (main character)
- Yagyuu Kyuubei
- Katsura Kotarou (Zurako)
- Yamazaki Sagaru (Jimmy Yamazaki)
- Hijikata Toushirou (22 years old)
- Okita Sougo (20 years old)
- Hasegawa Taizou (MADAO)
- Kagura (16 years old)
- Shimura Tae (20 years old)
- Kondou Isao (32 years old)
- Sakata Gintoki
- Being the Commander of the Shinsengumi, Okita Sougo claimed of himself as "the Emperor of the Holy Shinsengumi Empire." This, along with Sougo's look, is a reference to the Holy Britannian Empire from Code Geass.