THIS IS GENIUS, INNOVATIVE CONTENT, THIS MUST BE NOMINATED FOR GAME OF THE YEAR AWARD!
In all seriousness though, pretty good for a start, platforming is pretty alright, I didn't come into any major game-breaking bugs or anything so that is quite good. The music is well fitting for this style, it seems like quite a cute style and definitely the music fits with this, animations should be added too. Also the ending music was great and the artwork at the end to show the end of the demo was really well done! if you are going to work on this anymore I would say add some extra levels of new settings, overall definitely great for a start off demo game, also I read the Basic premise, the idea of the mysterious goose being chased by the duck to get their book back is a pretty amazing and funny concept, I was saying to myself, "its the opposite of the duck duck goose game, now the duck is chasing the goose? GENIUS!". I love this idea. Overall very cute game and a great start for a 2D platformer adventure.