I don't think I've ever had such a drastic change of feelings towards a character as I did towards Sachi over the last couple of chapters. She went from a character I symphatized with into a character I wanted to rot in emotional hell for a few years to repent her actions.
Like I even understood the first time she cheated, being confused about her personality, sexuality and just plain temptation, many people would falter under those circumstances....once.
Then the final chapter rolls around and we find out it wasn't just once, it was several times. Suddenly what was left of my sympathy toward her was replaced by loathing and anger. Then we get the scene where she tells Ruki about it all, no regret, no apology, no karmic retribution over her actions. No she gets a happy ending despite everything. That just didn't sit right with me. I think for the first time in forever I would have been happy with an ending where the couple I had been rooting for the entire series wouldn't end up together.
Perhaps the problem is that what their relationship is like after the final chapter is left quite a bit a mystery. Only clues we get are from the extra chapter where we have the scene with Remi where she flirts with both of them. Sachi hits her when she flirts with Ruki, but is more than happy to flirt back. Just left a very bad taste in my mouth. Sachi is happy to rip open the wounds left by her cheating just to tease Ruki. As a result I really can't see a future with them where Sachi doesn't cheat again.
If the author wanted to convince us that their relationship was going to be solid we really needed a chapter that expanded on what their relationship became. Perhaps about their graduation trip, with a scene where Sachi finally realizes just how much she loved Ruki, and how much she hurt her with her actions in the past, and finally truly apologizing. I think then I would have been comfortable with their relationship.
If the intention however was to leave us in doubt then good fucking job and fuck you author.
/rant over