Show of force
No one knew the biggest mystery in the future would be planned and decided willfully by Athena and Ling Qingyu. The mystery that threatened most second-generation scums appeared because someone laid a hand on a person they shouldn't.
Of course, although Ling Qingyu and Athena intended to strike at the lowest scum who abuses power, it didn't involve domestic violence culprit, nor scums who stood on several boats.
What they truly aimed was to fight against injustice, particular those with multiple victims on their heads, where justice was hard to lay upon them. Under oppression, revolution was the only truth, the same applied to justice—violence or vigilante would be the final option.
As for other victims, irrelevant to the case, Ling Qingyu could merely say sorry. She wasn't a justice symbol and her ideal wasn't up to the standard to the point where she would be helping everybody. Her action belonged to her desire.