Pls reply if you know

Mc has long red(?) hair, situation is pretty meta, she gets reincarnated as a child into a yaoi fangame of her favorite game where she's the sister of the yaoi fangame mc. Something something, the yaoi fangame has a lot of dark endings and she tries to protect her brother.

I remember she also has another brother, older but diff mother and they get in a fight where they punched and kicked each other