Okay this is old and has been stated in several comments in this thread, but this is driving me crazy and I need to rant, a lifespan of SEVEN DAYS for a sentient humanoid creature that seems to be capable of developing infrastructure and clothing is beyond fucking absurd and cannot be overstated in how utterly biologically impossible it is.
The shortest gestation period for a mammal is 12 days, longer than the LIFESPAN of a goblin in this world, a goblin who's gestation needs to properly develop a brain on par with a human's (which takes 9 months) within a matter of days.
How are goblin babies even a thing? There's no time to be a child when you'll be dead in 6 days, and they can't be born fully mature without splitting their mothers in half, so do they instantly mature within a day or two? How do they learn anything when their lifespan is so short, is their knowledge innate and passed down biologically?
Mind you those two examples our protagonist mentions to give a sense of realism to this fucking insane biology are cicadas and rabbits, rabbits which can live for a perfectly reasonable 2-5 years for a small mammal, and cicadas which actually infamously live for 17 years underground as nymphs and still for a few weeks as adults. Like this makes no fucking sense, you're telling me LITERAL RATS, COCKROACHES, AND FLIES LIVE LONGER THAN FULLY SENTIENT GOBLINS??????????????
The most apt comparison would be the Mayfly with a lifespan of only a day as an adult, an insect, which is no where near the same biological complexity as what's basically a small human being, but they ALSO live for a few years as nymphs, only living for such a short period of time as adults because their literal only purpose in maturing is to fuck, have babies, and die, which CAN'T be true for goblins because they literally have houses and clothes and a village with a government somehow????????
On top of all that, how would, or could, any sentient creature have evolved from a species with such a short lifespan, or if this is something they evolved after gaining sentience, why the fuck would it give any evolutionary advantage? The answer of course being that it wouldn't and couldn't because a species that can gestate a fully sentient human tier brain in a day or two is completely impossible and could never ever actually happen.
Yeah so in conclusion this is just absolutely fucking ridiculous, completely obliterates the suspension of disbelief, and is clearly just a lazy excuse for our OP protagonist to have a bunch of skills passed down to him with no regard for how this species makes any sense from a logical perspective, but I'm pretty sure we'll be swiftly moving on from this goblin village that somehow exists despite all known laws of gestation in a matter of chapters anyway so it's not like the author felt the need to think too hard about it