Both /choroy/ and Choroya are products of a relatively long journey, and in the latter's case it's resulted in a few changes over time. There are multiple and distinct iterations of Choroya, but all of them are the Choroya, even when different versions of her interact. Despite that, confusingly, it's not an Anon situation since there is supposed to be only one of her.
For a better understanding of Choroya, one should be somewhat familiar with the history of Chilean imageboard culture. Even by imageboard standards, information on this topic is sparse, vague, and at times even contradictory, so the veracity of the claims made in this thread cannot be guaranteed, but hopefully it should paint a picture as accurate as possible. The basic gist of it should be something like this:
1) Several proto-anon websites gather under 6-chan, the first "true" Chilean imageboard.
2) Due to various reasons, 6-chan eventually goes under. The community scatters into various alternatives that pop up and some slowly start diverging in culture.
3) Nido.org absorbs a large number of the refugees, owner Lamuel either buys out rival imageboards or tries to kill them with continuous shitposting.
4) Lamuel uses his e-clout to try and pick up popular femanons on Nido. If it fails or he tires of them, he starts rumours to ruin their reputation. Anyone who goes against the narrative gets instabanned.
5) /choroy/ is made partially to preserve the truth about Lamuel, partially to not be under his influence, partially as a way for Chilean anons of different imageboards to interact with each other.
Choroya was most likely conceived during the second part, on a site named Choroy Pride ("choroy" being a local nickname for the slender-billed parakeet, a parrot species endemic to southern Chile. Chilean anons took to identifying with it the same way a US American might with the American bald eagle), although some accounts claim she may have been around in some form as early as 6-chan itself.