If you can’t draw (that’s fine, I can’t, and plenty of writers can’t), your next free option is the public domain. All the art for my first HG submission was just me filtering, recoloring and applying effects to Public Domain pictures.
After playing the demo, I was considering trying to see how an otome vn game could work in the usual choicescript style. This is the art I made, using the same set of free resources and graphical parlor tricks I used to make for my first game. (It’s behind schedule now)
I’ll also say this. Your game did drive a discussion on how otome vn type of games could fit in the CS games we’re used to. I did play the demo of your game to the very end, simply because I was so intrigued by the concept.