I'm unfortunately not feeling very well at the moment. I have water poisoning.
I realize that you have no idea what that is for a fire fairy, so I'll explain it briefly. Since water is naturally detrimental to our health, it has to be "treated" with a special smoke chemical. There's a outlying section of Furier called the Smokers' Village where all the smokers live. Smokers are the fairies whose job it is to treat the water that fire fairies drink.
The water is put into buckets and the buckets are packed into huts with fire rings in the center of them. A fire made from some sort of special wood is lit and all the doors of the hut are completely shut and sealed. The water is left in the smokey hut for a day or two and then shipped wherever it is needed.
If a fire fairy bathes in untreated water, the effect is much like getting a cold. If a fire fairy drinks untreated water, something more like pneumonia develops. Usually drinking or bathing in untreated water is just a large inconvenience that lasts anywhere from a couple of days to a week (depending on the situation), but sometimes it is fatal.
The reason I have water poisoning is actually a bit embarrassing because it's my own fault. I was harassing Flame and he got fed up with me. He was standing right outside the supply closet near the torture chamber, so he just grabbed a glass of untreated water from in there and tossed it onto me.
I hate Flame. Always have, always will. He's so arrogant and mean to everyone. He tells horrible lies to the younger guards and slaves just to frighten them, and he's always telling the Fire Lord about things his fellow slaves are doing. He doesn't even know the meaning of loyalty except when it comes to the Fire Lord.
Flame really isn't so different from Coal actually, but somehow Coal is someone that everyone likes and respects while Flame is a hated bully.
I suppose it's all in how they come across. The two sparkers do a lot of the same things, but the way they do them is different. When Coal tells horror stories to the newbies, his eyes have this sparkle that tells you that he's only kidding around. When he reports something you did to the Fire Lord, it's usually out of duty and not out of spite or the desire to cause trouble.