Just looked through several chapters to find what tools the characters use to write with and I think they have pencils.
Chapter 40 was the best resource since Laios is writing notes the entire time. There's one particular closeup of the writing tip and it's thinner than the rest of the writing tool.
It can also be used to make rubbings.
This was the best panel I could find of the tool. It's from chapter 49. I think they might be charcoal sticks wrapped in cloth.
And they've been around for a long time because Thistle used one in his flashback.
Oh cool!!
It does look like charcoal sticks and I think that would make the most sense too!
The other possibility are graphite sticks but I don't think they would use those to write on walls? He's also not writing on paper he's using scrap wood or something, the way Kui draws it really reads more as a charcoal stick too
Also the marking on his nose is a smudge from the charcoal that's so cute
In the Blu-ray covers where they have their inventory displayed Laio's pencil shows up again along with maps, and Marcille has ink, quill and paper I imagine for most adventure's a charcoal stick would be more convenient than ink?
That made me want to try and figure out what Senshi uses to write in his diary and I think it's a pen? He got one tool in a mug and one in hand so maybe he has more than one writing/drawing tool? The mug might also just be a coffee wash with a brush for his drawing since some look shaded with that. Some of his drawings look like charcoal while others read more as ink to me... but I might just be reading too much into it and Kui just drew what she thought would look good.
