I haven't completed the drama but I think they the same concept as soon as he wakes up he has a family. He was surprised that he is actually married with a daughter.

Same pain, same heartbreak. When you don't remember the person that you loved the most. You will try everything to be remembered because you loved her. I can feel how the man tries to saved their love because the love that the feel is hard to let go.

The guy feels gay when they loved withvthe same gender without them knowing that they loved is truly a girl. I like how the girl hides their true identity .

They create their own justice, both have good intentions but in a bad way. They kill people that deserves to die.

Survival to the fittest, at the young age as high schoolers they managed to be mature enough to survive.

The same pain that we feel when we lost of beloved oppa. They have the same vibe the comedic side is super funny. When it becomes serious it really become very serious type. And the oppas are really never gets old even their age are very very old hehehe ? ? ?