UNDERTALE : The Story You Never Knew

In the game Undertale, we never really knew who Papyrus and Sans actually were. So, I have decided to make a theory about how they came into the picture. Note that this is just a rough sketch of my theory so if there is some things wrong don't judge me. Hope you guys enjoy this! And in the end, there is a YouTube video of my theory. Its not by me, but its similar to my theory.