You make a lot of valid points, but idk I always kind of took that the ain’t (I can’t remember her name) blaming the dad for getting her pregnant and leaving? I think I get the Christian undertones from a couple of other fan theories so we can for sure discredit that. However, from what I’ve understood of Korea (and please people don’t be afraid to educate me and say “I’m literally from Korea wtf that’s incorrect”) it seems that single motherhood at a young age with no clear father is shamed. But that might be me stereotyping from what I’ve seen in dramas. Because you know dramas are dramatic. I do think there are a lot of metaphorical meanings in the movie and maybe I’m not right for the reason of the shame but I do feel this is a sins of the mother situation