
I think that was his mom's spirit that helped stop him from going back

Yeah... Im wondering too whose that spirit... Perhaps theres a plot twist regarding that... Maybe his mom... was something related to the world of Eustil... perhaps Kouchi's mom was a descendant of long extinct dwarves in that world...That's why the spirit of Kouichi's mom prevrnt him in returning to his real world.
A previous chapter showed a man who I think is Seungho's dad looking at Nakyum's painting which Seungho's manservant passed to Seungho's brother when he visited. I think we're going to see a confrontation soon over Seungho's old habits that his father tried (and failed) to beat out of him (by beating either Seungho himself or Seungho's first love) when he was younger.