>>13752671Haato is the original vtuber and the owner of the body. Haachama is her sister (possibly twin) who died in Haato's childhood. In 2020, Haachama started to come back as a split personality of sorts and eventually took over the body, until February 2021 where Haato fought back full-force for a month (also where most of the backstory was revealed). After that Haachama time traveled back to August 2020 for some reason and then came back to the present in May 2021 where she fought with Haato again, possibly because GODCHAMA wills it. In August, it was revealed that Haachama became some kind of super-powerful god-like being after her childhood death, and through battles, deaths and rebirths, she gets stronger each time. By the time council debuted, she has gotten so strong that even concepts like Time and Space are scared of her.
That's pretty much the summary of Haachama's lore until now. See
https://tvtropes.org/pmwiki/pmwiki.php/Characters/HololiveHaatoCh for more detail.
