Yeah, I am emphasizing those words, since the whole prologue is about them.
And with that line,
If you read the explanation I wrote above, you'll know that the character believes blame is a concept that differs from person to person, whereas fault is a more concrete concept that we will be able to see it once we look at it from an outsiders view. What she's saying is that not only does she blame herself, the main conflict of her story will be completely her own fault. Context: the girl is Naomi's sister (the one on the rooftop) and Naomi kills herself after living with the main character. In her funeral, her desire to understand her sister, what made her kill herself, and what was going on inside that brain of hers gave her the ability to read minds (she actually reads peoples strongest emotions like sorry, joy, and lust)
She contacts the main character via some suicide notes, which makes the mc meet new people and help them with their issues. (it's kinda similar to Bunny Girl Senpai and Monogatari here) At the end of volume three, she goes insane. Hearing people around her without being able to take all the pain something she couldn't handle. Her name is Naya Mitaki which is a wordplay on Nayami Taki (Nayami means troubles and worries and Taki means waterfall). Naya can't wash away everyone's troubles, because she'll end up becoming filthier and filthier as time passes, so at the end of volume 3, she gives her own note to main character, telling him she'll off herself in three days, challenging him to do whatever she can. At the end of volume three, she finally wishes for the power to go away despite all the guilt she felt for not being able to help anyone anymore.
In this volume (volume 4) since she was given a supernatural ability due to her desires before, it's easier for her to get one again. In the events of the first 3 volumes, she ends up getting closer to mc, and after the whole drama of her power was over she starts wondering if he'll ever need her again and spend time with her (Because that's everything she'd experienced. She was always relied on. She was always the one helping.) She starts thinking that now that everything is over, she is no longer needed and starts separating herself from the main cast, which ends up creating another supernatural power within her. The ability to stop time. She ends up trapping mc and herself in a frozen world for three hours a day, just to spend more time with him. During the volume she is asked "are you sure it's not you" to which she replies with the monologue "I already know it's my fault"
So at the end of volume four, she finally admits that it was her, and in a frozen world that lasted for 3 hours, she ends up facing everyone she was never able to help, face her guilt, face her desire, see her dead sister again, who tells her "it was her fault that I died. You never helped me, you never helped anyone,, you just stood there, watching from afar"
She goes through a lot of heavy stuff there and accepts a lot about herself, and at the end, mc congratulates her on finally getting over the time-freeze thing, and asks her to be his friend, and from that day, he starts taking one request per day from her, to make her learn how to ask people for help since she spent years being the one understanding others and seeing their pain. He ends up being the one who understands her after ages.
So yeah, here's the plot till volume 4. So the part where she says "I am to blame and also it's my fault" makes sense...the part where she says "This story of wants and cravings has no value and there's no plot twists and it's pointless" also makes sense...because she always knew she was the one responsible for the anomaly. The part where she comments on a wrong truth from a wrong point of view makes sense, because she always heard everyone's truth and she began learning how sometimes truths can hurt more than lies.
the part where she says "it might be a mishap or a natural flaw in the flow of life" is a reference to how she got her power back then; the exact same words were used when she explained what happened at the funeral by the way.
the part where she said "it's quite selfish of me" hints at the way she sees herself, which is the main conflict of the story, and what causes the illusions at the end of the volume, where she faces all sorts of people she couldn't help, who kept calling her "selfish" for just staying back and being sad for them while they suffered.
"I am the secret twist, and I'm the one who will be confronting it. With a cold, expressionless voice, I will be confronting myself" one of the illusions she sees, is herself. The other Naya who watched everything as an outsider and tells her that it was her FAULT for leaving all of those people alone. So our Naya had to learn to not BLAME herself even if she had something to do with it all, which results in the frozen world to finally start moving again, and puts an end to that particular power...
ight...here's context, and now the image makes more sense...It might look like non-sense but there's a lot of context with what the character is saying that the readers will pick up little by little as they read it again to get full context. I'm okay with being vague. That's how this series is. I want the reader to think of the stuff the characters say and come back to them later, finding some new concepts and connecting them to something else and realizing what the character actually meant.