Responses
Exactly! Her grandma side story wasn't needed for the plot at all! If the author wanted Byul and Hyesung almost abandoned story drama, they just needed that flashback and that's it. In some random argument he brings it up, runs away, comes back and asks "what is the full story? Why didn't you want me?" and then they clear it up.

Ngl this is a common L from the author. Brushing Hyesung’s trauma and suffering under the rug is a poorly written move, if this is “byuls story” then why even include it in the first fucking place