I get that, at first I too wanted an Alex only run, and when I tried a more ‘permanent’ solution to Izzy after she drugged and tried to kill the mc...only to trigger a bad ending, I immediately recognized Alex and Izzy are a package deal.
I did hope once I was able to impregnate Alex, maybe that would be a turning point where Alex would be willing to leave Izzy for the mc. I now doubt that will happen, but the funny thing is somewhere along the way, I grew to care for Izzy too. Seeing different sides of her, gaining her confidence and even being there to emotionally support her through her own fears and issues with her mother, not to mention how much she does a 180 and develops strong romantic feelings for the mc apart from Alex... now I hope to keep the throuple going. I just have a nagging fear something tragic may happen to her before this story ends.
On a side note, do they know they are actually half sisters? If not, that’s gonna be an awkward reveal.