In the end, the brothers Hyakkimaru and Tahoumaru only had to endure one last thing: the missteps of their parents. When Hyakkimaru was born, Daigo decided to sacrifice him to the demons. Nui would have Tahoumaru later, but she never stopped loving her firstborn, and that ate at her second in its own way. Even Mutsu and Hyougou couldn’t replace the love of a mother that he always lacked.
As they continue their swordfight in the castle, Tahoumaru goes on about how the likes of Hyakkimaru doesn’t belong within the walls, and that unlike the post where Mutsu and Hyougou marked their heights over the years, there’s nothing there to prove his existence. This is ironic, as the castle itself is burning and crumbling around them, and all of that physical proof Tahoumaru values so along with it.
But even though Tahoumaru still has his human eyes, Hyakkimaru can still see the void in his brother’s heart; the same sense of lacking something as himself. They are no different, and despite their crazed fighting and bizarre modifications, they are both humans who have simply forgotten themselves, lashing out to fill those voids.
As Nui and Jukai enter the castle to try to stop the fighting, Hyakkimaru ends things on his own, not by killing Tahoumaru, but by sparing him. The demon eyes in his head still burn even after Tahoumaru accepts defeat, but he rips them out and offers them to their rightful owner. Hyakkimaru’s false eyes are ejected and his human eyes restored.
As a mass of demonic crystal surges with anger, the castle starts to come down, but both Nui and Jukai arrive in time to save him from being crushed by burning debris. He plunges his swords into the crystal mass, apparently exorcising the residual evil energy, but that also completes the destruction of the temple literally kept up by the power of those now-forsaken demons.
Jukai, Nui and Tahoumaru do not escape, but perish in the flames, while Dororo finds Hyakkimaru and the two climb up the well Nui used to gain access. Hyakkimaru sees Dororo with his own eyes for the first time and calls him—calls her—pretty, which really throws Dororo off. Biwamaru, who helped get them out of the well, stands with the two as they watch Daigo’s castle and surrounding lands burn in a purifying fire.
Once the flames recede and the smoke clears, Dororo is back in the village of survivors and invalids led by a few able-bodied individuals, including those he suggested start to live life without depending on samurai, using money instead of swords to maintain that life.
When they ask where that money will come from, Dororo says he’s got it covered. Dororo has decided, then, what to do with that fortune: use it to realize a community that runs itself, without fealty to some stern-faced lord.
As for the lord, Daigo is not quite ready to give up his quest to restore his lands to prosperity, no matter how many people, including Hyakkimaru again, he has to sacrifice to the demons in a new pact. That is, until Hyakkimaru takes a sword and instead of plunging it into Daigo’s back, pierces his helmet instead.
The helmet is a powerful symbol of Daigo’s status as something other than a mere human, so its destruction is a symbol of Hyakkimaru’s hope his father will live on as a human, something he too plans on doing. In the end, Daigo laments ever making the pact, as he now realizes he might have achieved prosperity simply by raising Hyakkimaru and letting him succeed him.
Bittersweetly, it’s not Happily Ever After for the duo of Dororo and Hyakkimaru. The two go their separate ways; Dororo to lead a new community in keeping with the legacy of her rebellious parents, and Hyakkimaru to learn how to walk the path of humanity after a lifetime of survival-and-revenge mode. With his new eyes, heart, and purpose in life, he has truly been reborn, and until he finds his way, it’s not safe for Dororo to be beside him.
However, the ending suggests that one day the two are reunited, as the young “boy” Dororo runs across a pier with a hopeful smile, he transforms into Dororo the older and more beautiful woman. At the end of the pier is a slightly older-looking Hyakkimaru, in all his human glory, welcoming her with a warm smile. It’s a shame a passing look is all we get, rather than an after-credits scene of the two conversing—but then again, perhaps their reunion is meant more symbolically, as something to which they both aspire.
In any case, both souls, once having lost and suffered so much, seem to be in a much better place, and have stepped out of the darkness and doubt and embraced their respective selves. While I wish we’d seen more of Dororo-as-a-leader, considering where we started, this was a logical and satisfying enough place to end.