>>150256200
It is weird because they are predominantly using anime specific nomentclature and concepts.
Like in the manga it is not just bad humans have the ability to become kishin.
It is specific in that only through the consumption of many good souls can someone end up becoming a kishin.
But then again we don't know the specifics there either.
Asura wasn't born as a demon weapon, but in his fear madness induced search for power he consumed his weapon.
This allowed him to consume souls not on Shinigami's list and contributed to his evolution into a kishin and also the Great Old One of Fear.
Crona on the other hand, only becomes a kishin after also having access to the Book of Eibon and BREW while being inside of Asura.
Maybe. It could be that Crona took on the features of Asura by overpowering Asura's will.
Regardless, the result is Crona becoming a Great Old One and representing the Madness of Boobs.
And there is seemingly more than one route to becoming a Great Old One in Soul Eater. Eibon achieved it through the Madness of Knowledge. Kid eventually achieves it through supplanting Shinigami as the Madness of Order.
And according to Ohkubo, there are ways of equaling and surpassing these GOO's through the cultivation of the self if Black Star is anything to go off of.