Big City Society Can Be Annoying
The pressure of stress can really build up in that atmosphere. It's chaotic, rushed and rude, irritating people are the norm. I can tell D-Fens was seeking justice against the negativity, but he went the wrong way about it. If he had been stronger in mind, he could have handled it as well as his own personal problems. It's easy to see that the stress got too much for him to bear which is why he fell apart.
He made it clear he was an honest-ordinary-Joe and didn't want to be branded as a "thief" or a "vigilante". He just wanted to attend his daughter's birthday party, but the situation with his ex put a block on that. He was seeking "justice" in his own way, but his perception got warped about it. He didn't win anything in the end.
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