I just finished it and it's a huge surprise, it's pretty well done!
The story is simple, but really funny and the ending was a total surprise. I never guessed that Agnes was the cause of the earthquake. I'm so blind! XD Regarding of the art, in general it's more beautiful than what we usually see in amateur visual novel. The character design is really well done. Belle and the harpy kind is pretty, she looks like Princess Peach.
However, Agnes is very simple, maybe it is to show that she is less important, I guess.
Finally, the best part of the realisation is the use of the animations, of the musics and the sounds. That giving a good rythm to the story, almost no dead time. Honestly, I didn't see too much errors in the realisation, the story is well written and I did not see too much mistakes and like Silvere the english is not my first langage. Maybe, I should listen more in my english class!
So good job and good luck for the sequel. I will look forward to see this.