Sekima Hiwatari (火渡赤馬, Hiwatari Sekima) is Captain Bravo's former teammate and one of the Alchemy Commanders. He is the leader in charge of Muto-assassination team. He has a bad temper and threatens to kill people, almost never plans things out first, and is willing to use the same tactic the enemy uses to beat the enemy. During the Muto-Assassination arc he said, "Unreasonable things must be beaten with the same unreasonable tactics." After Maruyama, Negoro, and Bravo were beaten, Hiwatari appears in front of Kazuki and co. to kill them. While Bravo tried to stop him, he released a flame storm that engulfed the entire construction yard thus leaving only the two silver skins intact. He went in shock after seeing Bravo sacrificing himself to cover his Silver Skin around Kazuki and Tokiko, and is angered by how Kazuki wants revenge. The two of them engaged in a fierce battle, only to have each of their attacks shielded from the other person by Silver Skin fragments. They were then stopped by Sakaguchi Shousei, the Asia leader of the Alchemy Warriors. Hiwatari is also known as the Alchemy Warrior with the strongest offense with his Buso Renkin Blaze of Glory.

His Buso Renkin is Kakugane XX, Blaze of Glory, which appears to be a napalm bomb with hexagons all over the bomb itself. This gives Hiwatari the ability to become one with flames, as such, the napalm bomb usually does not appear. The further the flames burn, the more powerful he is. As such, physical attacks will not work on him, as shown in his battle with Gōta. He was unaffected even when Motor Gear slit through his throat; instead of dying, he released flames from his wound to attack Gōta. Blaze of Glory is able to release a flame storm with a temperature as high as 5100˚C and a radius of 250 m. However, the flames still require oxygen in order to burn, and in the manga, it was revealed that in the thin atmosphere of the upper-stratosphere or in the vacuum of space, his flames will go out. The manga also reveals that, as Hiwatari merges with his Buso Renkin's fire, if the flames go out, Hiwatari will die instantly. Voiced by: Tomokazu Seki (Japanese), Kyle Hebert (English)

Source: Wikipedia