Mahiru

Mahiru is Yako's younger brother, he only appears in the anime.

About
Mahiru is Yako's little brother, who admired his older brother and Rokkaku since he was little. He blames Rokkaku for his brother's death and seeks revenge, so he teams up with Kohei to get closer to him. However, unaware to him, Kohei is the one responsible for Yako's death. Sometime later, Kyoji finds an old feather that once belonged to Raitonaitsunaito, suggesting that Kohei had been in Rikyu in the past.

Once Kyoji tells his friends this surprising news, Mahiru learns the truth that Kohei caused his older brother's death and allies himself with Reiji and the others. When Maiko asks Rokkaku why he didn't tell Mahiru the truth from the start, he said that Mahiru wouldn't have believed him anyway. Although Mahiru fought alongside with Rokkaku against Kohei, he still wasn't fully ready to forgive him for what happened to Yako. In the epilogue he is shown having apparently forgiven Rokkaku for what happened, flying alongside him and Gokakku, as Thundervolt's new partner.