The basic plot of the MC is that He, now She, is possessing a character in a game called "Lactea". The character she is possessing is called "Olivia". The main plot is her basically fixing the "past" by fixing regressors. Regressors are people who's memories are overlapping with their old and current one. Regressors are also the people who had a past relation with the MC. It's basically Undertale, except the MC is fixing her gen0cide route

why the f*ck does korean author likes to use "the reason MC is here because the future heroines turn back time to help him and accidently started the whole plot" nonsense, like olivia reincarnated to male MC and just so happen to play a game where she originally came from but also somehow all the runs that male MC did are actually the exact runs that olivia did within the f*cking game, like does the inital run did by olivia or the male MC, but since male MC cant exist without olivia dying and not regressing how TF does olivia still exist holding the demon god immortality and simultanously reincarnated to high dimension??, also how TF did male MC manage to replicate 1k+ olivia runs and also whos the dev that originaly update the game that causes the male MC to fall into the game world/ lower dimension, its hinted that olivia did it but then it raise even MORE questions on how did olivia managed to affect the higher dimension where she literally straight up says that "lower beings could only observe higher dimension and nothing more" so then who TF is responsible for all this shit???? Also why TF do korean authors are determined to create this kind of story, it happen in Omniscient reader too, anyway huge plot holes but whatever

The MC has to obtain "clues" to change her past with the NPCs which comes with many difficulties e.g. She has to keep the past similar enough as to not change the previous ending while also keeping in mind what benefits she could gain for the present timeline.

there was a huge battle before the demon king fight which I found utterly s*upid. They both had the same goal so honestly the fight was meaningless. Even the author admitted in the afterword that the 2nd half felt a bit lacking mainly due to his irl stuff getting in the way.

I also have some gripes with the fact that he turned into a girl when he returned to korea. I feel like if he stayed a boy there would have been a more interesting story.