These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Moral Event Horizon: O-Dog crosses this at the very beginning when he murders the Asian Store-Owner and his wife. Worse, he then uses the security footage as entertainment for he and his friends.
Rival gangsters cross the line when they shoot a young man and Caine without reason. Furthermore, it gets worse when one of them gets in the car and callously cleans the blood off the windshield with his elbow.
Nightmare Fuel: Several things that O-Dog and other gangsters do can qualify; to some extent they reach a disturbing point.