>>36743219>So much this. Lusamine is delightfully cruel and "in her own world" as a character. She is perfect as she is. By making her regret everything she did in the end, they eventually ruined her character But she was never meant to come off as a complete monster. Why would Lillie bother rescuing her if Lusamine was beyond salvation? Especially since there was nothing at stake in S/M's climax otherwise.
The game ended with heavy implications that Lusamine could change for the better. (Which is why Lillie went to Kanto to see to her treatment.) In addition to implications that Lusamine was high out of her mind in S/M while in USUM she was more tame.
If Lusamine was meant to be irredeemable, it would have made S/M's ending horrid since Lillie would just get more abuse for her troubles without you the player to bail her out.
USUM had her make that change on screen and had needed character development to warrant closure.
It seems that Lusamine's character was ruined from the start, especially since the anime and USUM made a few changes to her while keeping the core concepts intact.