Setsuo Miyamoto

is a former firefighter.

Background
During his time in the brigade, Miyamoto was mentally disturbed and killed four innocent people. After being caught and put on trial, he acted as he lost his insanity.

Introduction arc
On the final day of his trial, Miyamoto was deemed not guilty for his actions by reason of "insanity". As he was leaving, his hand began igniting, leading to him and everyone around him panicking as he began turning into a Flame Human. During the transformation, Miyamoto kills a bystander who was laughing at his misfortune before completing transforming.