I really don't like how this comic treats how Sayu going back home is a foregone conclusion. Everyone is convinced she has to go back home and "Face her past!" but what exactly does she gain by doing this? She'll return to an abusive household so that her mother can continue to emotionally neglect her or suggest she's somehow responsible for her friend's suicide?
What endgame is everyone thinking of here, exactly? What, is Sayu supposed to say "Mother, you shall treat me with love and respect as I deserve!" and then continue living under the same roof, being fed by this same person who could leverage all her power to just say "Nah"?
I understand that the current situation where Yoshida acts as Sayu's guardian but does not have custody over her is not ideal. At any point Sayu's mother could decide to file a missing person's report. Enrolling Sayu into a high school won't work without her mother getting involved, etc. Still, both problems will be solved if they just wait the less-than-a-year amount of time it'd take for Sayu to legally turn into an adult. Until then she can continue studying and reading school books. Once she's of age she could then go for a high school degree and explore options for further education or work.
I just don't see how "Go back to your abuser under the same circumstances that gave them the power to abuse you." is in any way superior to the current setup. Somehow there's not a single person in this comic who's willing to explain why this option is the only option and most definitely not a single person questioning why the alternative would be worse.