#Still try to manifest that all of them survive and agathario adopting billy in the end

[born-in-neverland03]

So we know Rio isn't able to kill Agatha.

And we know Agatha can't steal Rio's powers otherwise she would die.

So what if Rio just wants to collect her bodies and to get Billy because he cheated death. And it comes to a fight scene where Rio attacks Billy but Agatha goes right in between to protect Billy. She would start to absorb Rio's power (or her body would try). So Rio didn't actually want to kill her in that moment. Somehow she's able to stop it but it's already to late and Agatha breaks down and it ends with the kiss of death.