In every RPG you kill monsters, that is given. It's a staple of the genre. But why would you kill monsters? Actual in-world reason for it, not just video game logic of "kill enemy = number go up". What would be the point of killing monsters?
Because monsters are fuel, and have always been fuel. Humanity runs on monsters (or giants if you prefer).
The gears of industrial revolution were lubricated by whale oil. Call me Ishmail, because I will tell you about whales.
Whaling has always existed, for as long as humans could hold a spear, but it was the boom in whaling in the north sea that partially facilitated the industrial revolution. A single whale carcass provides a lot of resources, all ripe to be utilized by numerous scientific discoveries of the time.
In the early days, whaling was a brutal dirty job done by the dregs of society (remember "Moby Dick"?). You had a sail ship, a rowboat, a harpoon and your two hands. And once a whale was harpooned, you had to tug it along to your ship, and quickly extract it before it sinks*. Peel its skin like an orange, carve out blubber to be rendered... for sperm whales**, crack its rectangular skull and extract the spermlike waxy liquid, for baleen whales***, snap off the curtain-like teeth.
Imagine every time you wanted to fill up your gas tank, someone else had to fight a dragon with a handgun for it.
Whale byproducts were truly in everything. You lit your house with whale oil gas lamps and candles, put it on bread (as margarine), washed yourself with whale-oil soap, lubricated your watch, loom, sewing machine, wore whale bile (ambergris****) perfume, perhaps ate it as a delicacy, wore whalebone***** in your corset or stay, and carried it as an umbrella or a basket. And you most certainly used things made with newfangled industrial processes, all of which used whale oil as fuel and lubricant.
Whale persisted as a resource until the 70s, long after the discovery of petroleum. At this point, whaling was a much easier process, with steam and diesel-powered ships, harpoon cannons tipped with explosives, and air-pumps to keep the carcass afloat. No longer a grueling fight of man against monster, now merely an impersonal industrial process.
Now that whaling is done and over with (mostly), you might ask, how are we still running on bodies of giants then? Well, petroleum and its numerous byproducts (fossel fuels and lubricants, plastic etc) all come from dinosaurs. The monsters now come conviently pre-killed.
At least in the world of Fenestra, there is no industry, whale-powered or otherwise, so you may kill monsters and extract their resources to your heart's content.
* Whales, especially big ones, sink pretty quickly once dead. It's actually kind of a big deal for the ocean floor and its dwellers, and it's called whalefall.
** Sperm whales - like Moby Dick, or Pearl from Sponge Bob. If you snicker at the name, some might protest that its name doesn't actually mean sperm. Which is true, its named after the thick waxy liquid sloshing inside its angular head - spermaceti. Which in turn means whale sperm. Funny how that works.
It is in fact not sperm, it's probably something related to bouyancy and diving, but we cannot confirm because sperm whales are smart and also hate us now.
*** Baleen whales - whales are broadly divided into toothed whales and filter-feeding baleen whales (like the whale that swallowed Pinocchio and probably Job of Bible fame). Baleen comes from Latin balaena, related to Greek phalaina, all of which mean whale. So making baleen whale the whale whale. Platonic ideal of whale.
**** Ambergris - fossilized bowel secretions of a whale, probably a reaction to irritation (again, we can't study this because whales hate us now). Highly valued ingredient of perfumes and sometimes food. Valuable enough that some guy lied about Bahama's being the motherlode of ambergris and got it colonized by the British.
Technically not a byproduct of whaling, but nonetheless illegal in order to discourage usage of whale byproducts. Still illegally used worldwide nonetheless.
***** Whalebone - in fact not a bone, but the sort-of-teeth of a baleen whale. Closer to hair or nails in structure than to bone.
