I actually dropped Spider? in volume 11. I always hated the human side chapters with a passion and shifting the story more and more towards their side made me lose interest in the plot entirely. And when vol 11 was almost only human side it was the breaking point for me.

the same thing happened with SlimeTensei and Yuuki and his gang. Interestingly around the same volume number. Is there something in the 11-12-13 range of volumes that makes authors discard their series premise? Like year 7 of a marriage?

Anyway, my pro-tip for authors: if your series is called Spider/Slime/Sword/BigMac/whatever then your readers are reading for the Spider/Slime/Sword/BigMac/whatever. Don’t shift the focus away from what they bought your book for in the first place. It’s not that hard.