...why did Sora lose her memories of her sister? That's pretty nonsensical and melodramatic. Did the rest of the family forget Yukino existed as well? How about her burial, family registry, birth certificate? Wasn't she working before that? No one going to ask why she didn't come into work or why they're suddenly short on staff?
Page 15 Do you believe everything a scheming fairy tells you? This is lazy, rushed writing.
Page 28 Somehow I doubt that. It feels like the author wanted to do an entirely different story but created the villainess premise and title to follow the trend and get some popularity. Now that they have the readers they want to drop the pretext as quickly as possible.
I was wondering if this was a trend and I noticed this is the same artist as "I Became a Villainess" which also had an incredibly convoluted backstory involving cycles of reincarnation and the world ending if the "original story" did not progress properly. Are they just really bad with exposition, or are they cursed to work on terrible plots?
I can't say much about the author's intentions (since I haven't read the WN)
but I can at least give a
theory regarding your first question on why sora lost her memories.
Throughout Volume 1 (ch 1-6), we didn't actually know HOW yukino became lefina. We only know that she made a contract with God, and that her soul was transferred into Lefina's body, but the process and aftermath was not described.
Most likely, God didn't "kill" Yukino per se but instead completely erased any proof of existence of Yukino (ie memories, records, photographs). It makes things convenient for the author too, there wouldnt be any need for POVs or short stories from the original world since they dont remember Yukino in the first place.