this message may be offensive
gonna be completely honest with y'all, I don't know the backstory to Hollow!Ink's and Righteous! Error's existence. I went to the wiki, and from what I read. I concluded this is the backstory.
Ink was trained by Alpha, and Alpha never let him have friends or be social and all that. So Ink ran away and met the Unnameable, and he made friends with them. Finally thinking he had a friend, but in the end, he got backstabbed and the Unnameable corrupted him and he became Hollow!Ink.
At the time though, Error was training with Error 404. And instead of becoming the Destroyer, after Error 404 heard of what Ink had become from Alpha, he turned Error into Righteous!Error to protect them from Hollow.
And I made my own headcanon where Hollow destroyed HALF the Multiverse which glitched the balance somehow-
If you ask something like, "BRO HOW DA HELL DID YOU GET THIS STORY-!?? THAT'S NOT IT-!" I swear it was just my dumbass mind putting two and not two together and pretending it's perfect.