After Gojo’s defeat, his body was taken to Kenjaku. With his cursed energy technique reunited Gojo’s chopped body back to it was and managed to maintain his body and brain alive for his malicious plans.
Gojo continued unconscious as Kenjaku began his new plan: change vessel.
Kenjaku opened Gojo’s skull revealing his well maintained brain still active but not enough to make Gojo move his body and escape from Kenjaku.
Kenjaku activated his cursed energy once again to open his own skull showing his peculiar brain and his real identity. As that happened, he grabbed Gojo’s brain and removed it from his skull, leaving a big space empty of his head.
Kenjaku detached from his previous vessel’s head, to crawl into Gojo’s empty skull and reinsert into his body. Kenjaku inserted himself into Gojo’s skull connecting his stem into Gojo’s spine, slowly regaining mobility from his new body.
As that happened, he heard a familiar voice; it was Gojo, talking to him with what it had left from his cursed energy. Kenjaku kept still on his seat still regaining mobility into his new body.
Kenjaku heard Gojo’s last words while he created a tube to extract Gojo’s last energy so that Kenjaku could have Gojo’s full potential on his side.
The tube slowly grew larger and soon reaching into Kenjaku’s mouth to drink all the nutritious contents that Gojo’s brain has left to enhance Kenjaku’s cursed energy and finally defeat the exorcists once for all.