Just finished reading your Chapter 1. The story was an interesting take on things, much different than other Charmer fics I've read. I like the internal struggle Eria has, but you could be a little bit more descriptive when the "demon starts entering her head". Also if sheepish is Eria's natural voice tone, you don't need to say it every single time she talks lol. Wynn's personality made me laugh though, I wasn't expecting to hear half the things you made her say.
One thing I do have to say (and I'm not sure if you have fixed this in your later videos) is that the pacing of the text is downright painful. The amount of text on screen at once is way too much to read and comprehend without stopping the video every two seconds. Dunno if this is what you intended or not, but I can see how this could get annoying to some people, especially if/when you use background music. Maybe you should put smaller amounts of text on each slide, and just keep the picture in the background the same for those slides.
I'll be reading some more of it later, and give my feedback on them then. Good job!