I have been running session of the goblin slayer trpg for about 4 weeks (3 sessions in total) and there are still many questions I have about it, but the biggest one right now, is there any way at all to increase your statistics?
It's been a while since I glanced over that book, so I'm afraid I don't have a definitive answer, but Japanese RPGs tend to favor much shorter campaigns than traditional US RPGs. I would not be surprised if it does not have stat progression, as the Sword World authors probably didn't intend for a character to be played for years before retiring, and Goblin Slayer is based off of Sword World rules.