Ah the whole thing with technology/inventions! I remember putting in that Marui was washing the dishes in one of the PoT/FE chapters and then re-reading it for an error-proof and going "What? Do they even have running water or a sink?". I gave him a water basin instead lol. And lights... I have to keep reminding myself to use candles and torches. Although some of the rooms in the castle have these glass containers with light magic trapped in them courtesy of Yanagi who has some small skill with random handy light spells XD

Good luck good luck on the story! How much more do you think you have left to write? I hope to start reading sometime soon because I have slightly less distractions now.