She was transferred to a world where she never existed cause the girl that asked her the question is like a god or something and tells her that it's an alternate reality where the dude didn't die since she asked to be together with him she got transferred to that world but she wasn't a part of his childhood like in the other one. Reading the story though, it feels like if the dude is slowly falling in love with her even if he already is going out with the childhood friend from that world. The mc girl even said that she didn't mind that he didn't remember her, all she had to do was get him to fall in love with her again. As of the latest one, it also looks like somehow the memories of the other reality are becoming the memories of the dude that is still alive.