Trueblood El Fuego Interior with hemophilia. Thousands of people undergo voluntary euthanasia every year, with some time and effort I could probably convince a few dozen of them that letting me burn them to death to fuel my magic would give their deaths more meaning than just overdosing on morphine and drifting off (it would probably help if their organs were rendered useless as transplants by their disease).
With immortality and a cadre of fire monsters on my side I've got a handful of options. Go full warlord and carve out a slice of Africa, sell their services to world militaries, or avoid the moral quandries of warfare and sell them as firefighters and energy sources