First of all go to Sleepytime Manor at the highest point of the map where the yellow duck is.

Then you'll have to approximately line up with the two trees in yellow dots on the image,
make sure to have good speed but not too much, because if you do you'll probably go too far.











After that, fall for 2-3 sec then dash and aim for the nose of the moon














Right as your dash ends, start to fall and aim for the black box, this could take several tries because of the size of the box.




And there you go ! You've successfully skip the entire game !
(Although I haven't tried with a fresh save I think it should work too)

Here's my video that shows you how to do it:

Altough I guess this was not intended by the devs to be kept in the released version of the game it's still funny that a trigger box can be here.
Probably gonna be fixed anyway.
Found it randomly while trying to see if the moon was a real object or not lol, I don't know if anyone else found that but just in case, I wanted to make it as a guide for anyone interested !