Redeeming villains was a common trick in anime.
When it came to that, Naruto had the most to say.
Orochimaru, Itachi Uchiha, Nagato, Obito Uchiha—one villainous boss after another had ended up thoroughly redeemed.
But in Hao Shuai's opinion, Nagato and Obito Uchiha were two people who could never be redeemed, no matter how hard anyone tried.
He didn't think that because of how many people they'd killed or how many terrible things they'd done as villains. It was simply because they'd both murdered their own mentors.
As the saying went, "Once a teacher, forever a father." Back then, Minato had been Obito's teacher and had cared for him in every possible way. Yet on the day his teacher's wife, Kushina Uzumaki, went into labor, Obito controlled the Nine-Tails and tore it from Kushina's body, indirectly causing the deaths of his own teacher and his wife. That was repaying kindness with treachery. Unforgivable!
And Nagato was even worse.
Jiraiya had done everything he could for Nagato. First, he'd rescued Nagato and the others from Orochimaru, then diligently taught them how to survive and use ninjutsu. He'd practically given them a new lease on life.
And yet~~
Just look at how Nagato repaid Jiraiya.
When Jiraiya came looking for him, Nagato broke his arms, crushed his throat, and covered his back with black rods. In the end, he was left in such a state that not even a complete body remained, and he didn't even get the chance to be revived with Impure World Reincarnation. It was simply horrific.
By comparison, even though Orochimaru had also killed his teacher, the Third Hokage, his love for him had truly run deep.
So when Hao Shuai saw Pain, he felt the urge to slap Nagato to death.
Unfortunately, Nagato was too good at