Oh fs, that's also my theory too and that the original ending must've been something really tragic. I'm just wondering will the original protag of the original novel be made out to be an antagonist late cuz of the changes or something cuz that's a trend I've been seeing.
Honestly thinking about it now, I feel like they wouldn't pull something like that. There might be a happy ending for everyone (I really hope so)
One of my most favorite things about this manhwa is that they didn't turn the holy order into some corrupt organization like they do in other manhwas (๑•ㅂ•)و✧
[SPOILER]
I forgot the ending but I remember the epilog, it was a happy ending. It's true Ruri was a transmigator.
There were some kind of competition with other transmigator to raise their child to have a happy ending.
The reward is to go back to their previous world if they wanted to.
Ruri's existence was in the prophecy book. That's why she disappeared when Bunny was dropped off in the orphanage.

This is just so good and refreshing to read!
If possible could someone spoil me if the og FL is an antagonist or not cuz I got a bit of fatigue from that type of trope ;-;