It is about what the changed event maybe, and I feel like it is that part where Hanako, aka Amane back then, tried to play outside with tsukasa, and fell very heavily sick. By that time, Amane caught a pneumonia, which on their timeline, back on early 19's or late 19's, it is not curable yet. Amane is about to die at the time, when Tsukasa qoute unqoute, "sold his soul to a spirit" that offered to give whatever he wish. (it is the same spirit that is connected on that female sacrifice thingy) My theory is that either the "amane dying" event is erased in this world. In that way, Tsukasa wouldn't sell his soul and turn into something Amane despise, he would be that ol' lil' chum of a brother he is, and so on, Amane wouldn't be Hanako, there wouldn't be mysteries by the student's rumors, there wouldn't be the 7 Mysteries, and Hanako wouldn't meet Nene, Nene will not be engaged with the supernatural, they wouldn't go destroying bounderies, they wouldn't lead on Aoi's (the girll) life span being sacrificed and everything up until now.
But there is actually also a possibility that the SPIRIT is the one that is removed in this timeline and that the spirit is actually the very root of everything not rlly Tsukasa...so yeahh
NAH NAH IS IT JUST ME THAT THOUGHT ABOUT THAT SCUMBAG OG CALE HENITUSE FROM THE BIRTH OF THE HERO WHO IS JUST A BAS**** OVERALL?!?!?! DONT TELL ME ITS JUST ME
OMG DARK ELF ALBERU (Alver) IS STILL THE BEST OF THE BEST!! AND JACK AND HANNAH THEY'RE FIRST APPEARANCE (i mean Hannah appeared back then, BUT JACK!!!)
Spoiler!
Those who dont know about Jack and Hannah, they're basically the Sun G** twins who is a swordsmaster(hannah) and a healer (jack). They're from the Moguro Empire, and yeah i rlly wanna take this story further but i cant---
THIS IS SO GOOD!!! This is really refreshing, after encountering a lot of bls that moetly focus on fuc****, slowburn like this is really refreshing i love itt