I agree! It's like the artist forgot they had to have incorporated this character and one day just woke up and went "shit! the priest martyr guy!" They have had other late added flashbacks but this one was a whole new character, it stands out like a sore thumb.
I don't understand why they did it like this...
That’s how it was introduced in the novel but it didn’t stick out like a sore thumb. There was always religion complete with biblical scriptures throughout the Korean version of the novel. Ines was always asking questions about her past suffering and repeat lives. The novel is also written progressively. There will be other new characters forthcoming that will stick around to the end. There is a reason why they appear when they do. The story is like unraveling a mystery. There are still things that Ines doesn’t even know that will be revealed later.
This was a very weak execution, in my opinion, when he should’ve been built up to us as readers who have been having questions about the powers that be that permeate this story. So many webtoons do this too and it looks so rushed to me but that’s just my opinion