This is ridiculously dark, the parents killing all the kids, its really quite overwhelmingly dark, especially as making that situation work was almost impossible, so they did it just to prove how evil the villain was and give us a sense of despire before the heroes win, but its too miserable for us to really like the heroes winning,
I hate when kdramas have good plots like this and the victims have fighting skills and so much more tenacity but they dont go full Glory mode and kill those that harmed them but pet them go after a few punches but the villains OH MY they write them despicable. I mean they harm, kill and more and then in the end just get off or get placed in jail its like ass backwards 😂 if you have the word revenge in the description let there actually be revenge 😂