I've lurked awhile, finally made an account yesterday just to chime in what's already proly been said.
Bella's got two options:
Come clean in the thread, just say she did it, that she's got sick, fucked-up fetishes and was excited to learn that Chris did what he did (which was way better than her plan to become part of this mess) and satisfy the hive - because we already know all of this. If she gets into legal trouble, let her parents help her deal with that with their connections and money if they want, and suffer some social stigma for a few years. In this way, she'll have some control over the outcome because she'll lean in to the thing that's burning her life down. Give the animal the blood it wants, and it'll stop being so hungry.
or
Disconnect from the internet, let this thing burn till there's nothing left to burn, and deal with whatever consequences come from that, which very well could include some social consequences that are worse and longer and farther reaching than if she'd used the only control she had and confessed. The internet is not easily redacted and those things will keep being dug up and last for years - and she could likely become the next Chris Chan because she's got that inability to step away.
Either is better than her pitiful attempts to absolve herself with sock puppets that just keep the wheel turning.