Na-Ra was the one who had started the fire that killed Dr. Dumb's dad. She had accidentally knocked over the stove…
yes maybe nara started the fire . that time i guess she was a little kid and probably was an accident .... but her mom knew all about it ,.. so her mom is responsible as a guardian for the fire and the death of doctors father .... but she kept her mouth shut and avoid the penalty ....
miran case = I think everything started with miran s father . she was forced to end the relationship with doctors uncle [a nobody at that time] and she did . later found out she was pregnant from the uncle but she kept it a secret from him and everybody else , only her brother knew [jaein s father] . her brother came with the idea to pass the baby as his to his wife , hiding the bio-mom .... and miran was convinced to see her son as heir . then she maid a garbage marriage for YL group s sake and after few yrs suffering she was divorced . we know the rest of the story .......
gyeongja s husband has to think again about his attitude/character and how wrong he is ..... he almost cause the death of his wife and her friends ...... and he already has destroyed his wife dream and career ..........
seri wants to find her bio-mom , cash her assets and leave that family and go with her bio-mom ............... what a shock coming up if her bio-mom is the ceo-sister .......
Su Jeong’s decision to bring Seol Hui to the site of Mi So’s death isn’t just about grief—it’s a calculated…
i think suyeong just pick a place that nobody can hear them and she just wants an informer against her sister . taeyeong was there for scenario purposes as you said and i think nobody saw the collapse [ unless there is a cctv ] ...
Celebrity 
her brother came with the idea to pass the baby as his to his wife , hiding the bio-mom .... and miran was convinced to see her son as heir . then she maid a garbage marriage for YL group s sake and after few yrs suffering she was divorced . we know the rest of the story .......