Just ACTUALLY drop it

If the plot confuses you, you're not just putting any dots together, you're just reading words and not understanding or finding anything. Taesung's grandfather has been mentioned a few times by Taesung's mother in the past seasons, he's also been the catalyst to Haebom and Taesung's young bond, allowing them to grow up together. You guys are so used to so much fluff and good things in someone's life that you get so mad when conflict and chaos comes. THIS is the part of Haebom and Taesung's life where they actually experience that chaos unraveling itself and also where they see and experience the cruelty of Taesung's grandad first-hand. Introducing them to something that's hard to destroy, a hardcore enemy unlike the little softcore problems they've had in their lives. THEY FINALLY EXPERIENCE THE CRUEL AND REAL UNSUPPORTIVE SIDE OF THE WORLD TOWARDS THEIR RELATIONSHIP!!! SOME OF US are actually curious about what happens beyond the happily ever after that had no flaws. If it's not for you, don't read it. Drop it, dumbass.