In the "Pet the Doggo" level, if you zoom out in photo mode a message can be seen on the side of the platform that reads: "I made this level for my GF ;D".
Contributed by PirateGoofy
If you explore Level 50, you can find a game developer named Dane in a closed off office-like space where he will say that the player can stay as long as they don't do anything to his computer as he is working on the game as the player is playing it. If the player does end up raining on the computer then they will get abruptly booted to the title screen.
Contributed by PirateGoofy