so i think bea has multiple personality disorder, and chihiro is her other personality.
>her sister, Chihiro, threw her into the internet on October 2019 as a result of a fight and trapped her in therea metaphor for a personality split, where chisato gets literally trapped in her own mind by a more dominant personality. also explains the shift from a obvious dislike for chihiro (mentioned by bea once) to an acceptance as they both strive to
COEXIST.
the video here
>>3067738 is another hint, notice how last character is basically a carbon copy of menhera twitter bea.
it all makes sence