Moral Event Horizon: Shigeko trying to provoke Rio into suicide. Even worse is, upon being called out on it, she not only showed zero remorse for it, but appeared to be genuinely offended that her husband and Shoumitsu were "taking Rio's side" on the matter.
For the film:
Cry for the Devil: Kang-do has committed a lot of cruel and despicable acts, but it gets extremely hard not to feel bad for him, as during his Villianious Breakdown when he becomes emotional over Mi-sun's "supposedly" missing and death is heartbreaking to watch.
Signature Scene: The ending where Kang-do chain himself to truck underneath, leaving a trail of blood on the road while the truck drags his body.
Too Bleak, Stopped Caring: There are almost no sympathetic characters in the movie- Kang-do is a cruel, violent jerk, Mi-sun is manipulative, and all of Kang-do's victims are somewhat pitiful but vindictive and weak-willed. Combined with the brutal violence, this makes the movie a tough watch.
