Granted ml 9 wishes for something in return (ml uncle thinks it wants mls soul so he sealed it but now it unsealed itself )
According to the ml's uncle, it will take the ml's and mc's lives in exchange for having connected them together.
My guess is it calls itself "spirit of salvation" because it helps humans defy fate by granting them the wishes that fate did not allow, even if changing heir fates ends up causing those humans' deaths, as a result: I imagine it as a kind of automatic auto correct of the universe after a "computer virus" (aka salvation spirit) caused a "computer bug".
Can anyone tell me, what really was the deal with salvation spirit (like what was the deal and what the spirit wanted in return)? I am too lazy to reread the chapters.