There's starting a cult, and then there's having some sort of mildly psychic ability to suggest things to people and have them stick. Making people think their ideas are their own when they're entirely not. It's a concept he can grasp even if it's not a power he's ever seen - and in fact he can imagine that sort of power functioning as a devil fruit, but a very, very powerful one. A terrifying one.

"A cult controlled by one man, able to direct them at his will. I can see how that kind of power could be abused," he says. It's the sort of power that would in fact make such a person awfully hard to contain if Gregor's world doesn't have the tools to negate such abilities, the way the Marines do with seastone to disable their prisoners.

Of course, he does know to take some of this with a grain of salt. People can tell stories here. He certainly has. Odd story to make up in order to justify a man's death, though, which suggests there's probably truth to it.