I apologize for replying a bit late, but thank you very much! Granted, the coding of the wikia (and the info about the places, settings and whatnot) are done by someone else. What I'm doing is pretty small in comparison, but I wished to spruce up the wikia however I can either way.

As for the sprites, half of those sprites can be found in N+C's official website (https://www.nitrochiral.com/game/slow-damage/), mainly for the main and supporting characters. For the other sprites (e.g. the more minor characters), they can be found by extracting the game files, which someone has done and created a link for; although you will need to have an account in the Aarinfantasy forum to access said link; it's a general rule there to not share links outside the server and I would rather not risk stepping on toes (also, sharing links to VN assets on Twitter can be rather risky and might attract trouble).

Though on the bright side, it's very easy to make an account in that forum and the search system is also pretty straightforward, so you can find the link in no time once you are able to log in there. ᵔ ᵕ ᵔ

And just as a tip: because of how Slow Damage has the characters blink and move their lips, the sprites are blank-faced by default, with the image files for the lips and eyes, respectively, being in a separate folder. To create those sprites, you would need to overlay them manually.