Seimei takes the risk of being dismissed as lead guardian of Edo by undoing the Shikigami placed throughout the city, and fueling himself with all their power to face Douman. Their fierce magic clashes, and Douman is forced onto the defensive as Seimei's techniques overwhelm him. Just when the battle seems over, Douman recalls the history between his family and the Ketsuno clan as repeatedly told by his father.
It continues to rain as Seimei and Douman prepare to dual. They each start off by firing spells at each other and Seimei is able to push him back and knock him out of the ring. Douman prepares to counter with a seal attack but Seimei has over a thousand of his own to attack him with.
As he’s caught in the attack, Douman remembers his childhood being told the legend of an ancient demon with two Onmyouji brothers working together to beat it. They were split up over a princess, where the younger brother was in love with the princess only for his older brother to take her away. He killed them leaving their child, and as he grew old he realised he had become the same demon that he and his brother had fought. He was then shot with a bow by the older brother’s son and the older brother’s descendants would later become the Ketsuno clan while the younger brother’s descendants the Shirino clan.
When he was a child he had been friends with Seimei but when his father found out he told him to attack him and Seimei beat him time and time again with each challenge. One day after being defeated, Christel appeared before him and gave him something. And when they got married it appeared continuously. As he remembers this the tattoo on his face begins to cover his entire body.
Douman stands as the demon the brothers had once fought and attacks in a blind rage. With no attacks working against him. He easily defeats Seimei like this and Gedomaru stops his familiar from running in, believing in Gintoki despite only having one ball now. As this happens he stands up and takes up his bokuto.
Kagura climbs up to save him and gets swung around. Seimei tells Douman to end their fight by killing him and tries to make him remember that he loved Christel. Only for him to blast him in the face as the demon takes hold. The smoke clears and Gintoki stands in front of Seimei, his bokuto glowing.
- Shirino Douman
- Ketsuno Seimei 結野 晴明
- Douman's father (Flashback)
- Ketsuno Crystel (Flashback)
- Shimura Shinpachi
- Sakata Gintoki