Wow, you have a nice piece of work here. The graphics are simple, yet charming; the music and voicing, clear and sound.
Two would be my advices: Story, and controls. Instead of just cyclical references to the mountain alone, it would be even nicer if there were some kind of story about Edwin, his past, his persona, etc, engraved on the stone and read while the player climbs it up.
Regarding controls, my bet is that it'd become way more fluid to have them configured to asdw + spacebar + another key for being pressed by the right hand (since the mouse is not used in the game). That way, the player will place their hands more naturally on the keyboard, thus enhancing gameplay.
I'd love to see a sequel involving such mechanics, and I even think that, by giving it a meaningful story, it'd be even viable for porting it to mobiles. I, for one, would buy for a bold story enveloped in such a pleasant graphic environment.