From Geto Suguru's perspective:
Gojo Satoru had lost his mind.
Geto Suguru was absolutely certain that Gojo Satoru had lost his mind. After learning Reverse Cursed Technique, Gojo didn't care one bit whether Amanai Riko lived or died. With half his body covered in blood, he pinned the back of Geto Suguru's head and shoved his tongue into his mouth. Geto had already been beaten half to death by Fushiguro Toji, and after Gojo, now fully healed, had him in his grasp, he couldn't break free at all. Even when the kiss nearly suffocated him, Geto couldn't push Gojo away. He felt like he was about to lose his mind too.
What was he doing? What was he doing? Wasn't there anyone who could do something about Gojo Satoru suddenly going crazy?
So Geto Suguru was certain that Gojo Satoru had lost his mind.
From Gojo Satoru's perspective:
In his previous life, he must have been out of his mind to let Geto Suguru go. In hindsight, he should've knocked him out and locked him up right after they split at New Star. Then Geto wouldn't have been so disobedient and gone off to become a cult leader.
If he wanted money, all he had to do was ask. Gojo could give him the entire Gojo clan.
Who could understand how devastating it was to have to kill his best friend with his own hands?
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