A tall tale I heard from my elders: Once upon a time, there was a monster. He was so hungry and fueled by jealousy, he’d only take and eat what is most precious to others. That include babies. Yes, he’d sneak in someone’s house in the middle of the night, kidnap babies, and eat them.
So to throw off the monster, the locals decided to call their most precious things by the most insulting names. Children would have baby names like that of cats and dogs until they are coming of age.
When tragedy strikes, and there are no explanation that can satisfy such nonsensical cruelty, people find comfort in superstition and religion. Which kind of make sense that Sseureki got his nickname. Given that Na Jung’s brother passed away at such young age, (12 maybe? Hoon did not look like he’s hitting puberty just yet. ) it is not unusual practice for Sseureki’s parents to give him this nickname.
Sseureki’s unrefined behavior serves three purposes: He really wanted to emphasize that he’s there for Na Jung and parents, but had no intention to replace Hoon, who seemed to be the serious one portrayed in the flashback montage. The behavior also serves as a forcefield, shielding off his true self, hiding his softer and sensitive side, maybe also to hide his grief of losing his best friend Hoon. A simpler explanation would be he really want to complete the joke that is his nickname, and really living up to his Oscar the Grouch bit.
Right now, I’m not on any ship as to who Na Jung’s husband should be. I am fine with either ChilBong or Sseureki. We shall see.