Responses
i think hes just generally a huge asshole (based on how his reputation) and he thinks that Sejin is conspiring with his family to marry for financial gain so he basically thinks Sejin is trying to sell himself
I think certain parties like his father or Sejin’s brother may have blip some lies to Ido to try to wedge a gap between a married couple. Plus he may have already had prejudice towards omegas we don’t know yet
I know this is the flashback portion of the story but it just doesn’t make any sense on why he’s treating him that way.. Maybe it just hasn’t gotten to that part yet that explains the reason but Ido’s treatment of him is just so unprovoked.