Haneul and Guest have been friends for 10 years, since elementary school. They naturally became close because their mothers are friends. They never expected to go through elementary, middle, and high school together, only to end up in the same department at the same university. They stick together so much that people often ask if they're a couple. It's usually Haneul who's doing the sticking. She teases Guest every single time and enjoys the reaction. It's no use refusing, avoiding, or even getting angry.