After Perona bandages what remains of his left eye, she confines him to rest and stays with him to ensure it. Left with nothing to do, Zoro's thoughts invariably drift to Kuina.
For the first time, he truly understands how she must have felt that night, when she talked about how she could never become the world's best swordsman because she was a girl. Mihawk certainly doesn't have any missing body parts. Nor do the great majority of people Zoro's met so far, except for Crocodile, but he's got a Devil Fruit to compensate for that.
Of course, like he had told Kuina so long ago, skill is what matters. Something like this doesn't mean anything, and it won't, eventually. Crocodile had certainly got far enough despite missing a hand. But right now, the reduction in Zoro's field of vision is still new, unfamiliar, and he's lucky that he's still got more than a year left before he is to rejoin his nakama.
What would Kuina say if she were here now? Zoro thinks that she might laugh at him and call him weak—she had certainly always been stronger than he. Or perhaps she would understand how he feels at this moment.
Zoro will never know.
The first time Zoro sees Tashigi, he is taken aback by how much she resembles Kuina. He has always imagined that she would have become a marine, a natural progression from the order of the dojo; he's certainly never been able to see her within the chaos of piracy or the selfishness of bounty hunting, never been able to see her need to turn herself to either, when she had always been one step before him.
There is a clumsiness, a weakness to Tashigi, though, that Kuina never had, and Zoro cannot imagine ever falling to someone like her. This is only confirmed when he meets her again at the sword shop—she does not have the self-assuredness that Kuina had, a self-assuredness that comes from having never lost, from having never had to bend to the might of another.
Of course, it's not as if Kuina would have remained without defeat if she were still alive. The scar across his torso is proof enough of that. But Kuina's losses would have only served to spur her on toward their goal, Zoro is certain, just as this everlasting mark of his defeat does; she is him, only better, and so it must be. Death is the only thing that can stop him, and it was the one thing that had ended up stopping her. Thus, defeat would never have been enough to make her become so clumsy, so soft, so uncertain of herself.
The fact that someone could wear Kuina's face yet lack her strength is a mockery of everything that Kuina ever was, everything that Kuina had ever wanted to be, and everything that Kuina could have become. She would probably have detested it.
And yet, despite all of that, here is still undeniable proof that he had been right that night, that it's skill that matters and not the form one's body takes.
Zoro proves it in the upcoming months and years, over and over again.
'Why do you limit yourself to the same sword when you use Ittoryu?' Hawkeye asks. Zoro does not answer because the only thing he could say would not mean a thing to Hawkeye.
Because what other sword would I use?
Wado Ichimonji is the only tangible thing he has left of Kuina, and so it has always been natural for Zoro to use her sword when he needs only one. (And for years, it had been the only sword of worth that he owned.)
But Zoro also knows that Hawkeye is right to ask. Zoro has only one eye now, and he's found that sometimes, Wado Ichimonji doesn't have the bite he needs to compensate for that. Yet even still, he hadn't been able to envision not using Wado Ichimonji for Ittoryu.
It would have felt too much like he was turning away from Kuina and everything that she had given him.
But Hawkeye's words have reminded Zoro that that is not quite true. He still exists, and they had made a promise together.
Kuina's will still lives on in him.
Zoro sheathes Wado Ichimonji and draws Shisui.
When she appears in his dreams, Kuina always looks as she had on the last day that he had seen her. Zoro is discomfited by it whenever he really thinks about it—she is older than he, and yet he is the one who grows ever older, whilst she remains forever young.
It's a balance of power that unsettles him.
He welcomes her anyway because this is the only way he can actually talk with her, even if she is only something that his mind has conjured up. Kuina is wearing one of the long dresses that Perona has begun wearing recently; it's strange seeing it on her, but Kuina wears it as if she's always worn it.
'Hey, Zoro,' she says, her voice forever that of a child's.
'Kuina,' he says in response. It's the first time he's seen her in his dreams since he's lost his left eye, and it feels strange. Zoro wonders whether he'll feel the same way when he first sees his nakama again.
'How are you feeling?' Kuina asks.
Zoro shrugs, and then, 'Stronger.'
'Yeah?' Kuina asks, smiling. 'Show me.' It's a sunny day, and she sits down on the grass and waits.
Zoro does; showing her his new techniques has always been easier to do than anything else, and he sits down next to her when he is done. They don't speak for a long while, until Kuina says, 'Let me see your eye, Zoro.'
He turns toward her, and she reaches her hand out, traces the scar on his face like she had the scar on his torso months and months ago, soon after he had got it.
'I can't believe you got another one,' she says, teasing.
'Things happen,' Zoro says with a shrug. This is not quite the reaction that he had imagined (but then, this Kuina is something conjured up by his mind; she's not real).
'Yeah, and you'll prove to me that you were right, won't you?' Kuina asks, now serious.
'Of course,' Zoro says without hesitation.
'Good,' Kuina says, and the smile on her face is the same one that she had worn when she had declared her 2001st victory over him, fierce and unyielding and challenging.
Zoro can only stare because the sight of that smile never fails to remind him of his purpose.
Kuina rolls her eyes. 'Stop staring, Zoro, and tell me everything that's happened since the last time we talked.'
Once, when Zoro was a kid, he had made a promise.
'Hawkeye thinks that I've found something greater than my own ambition,' he tells her.
'Then he would be wrong,' Kuina says, and the smile on her face is that of a predator's.