User blog comment:JustSomeDude.../790 & 791 - Break/@comment-21119641-20150628163108/@comment-24.235.56.170-20150629215102

Like seriously, why would you think I'm talking about Vivi when I say "a devil fruit user"? I mean, you're making connectons where there are none. That's just irrational.

Robin and Viola both started working for the kingpin of an underground organization as young women in order to survive, but after years of service, were revealed to have resented him and even to have wanted to kill him all along. Both women spared a Straw Hat at a vital moment and then sent them to a fight with the boss which they lost, but survived due to last second Deus ex Machina. Later, during the last big fight, when it looked like Luffy may not be able to beat him, they finally took their chance to try to kill him but were easily defeated. This happened right before Luffy suddenly arrived to save them, thereby initiating his final confrontation which ended the kingpin's reign of terror on the island once and for all.

And their names both have 5 letters in them. So they've got that going for them too, which is nice.