In a dramatic sense, her father actually calls her a weakling when he finds out. He only "cared" for her because she's his successor.
Bullied girl can't take it anymore, so she sets up a smarter plan. Not even Aizawa knows, that's because she knew he's aware of the bullying. She manage to piece out the connection? (Like wtf how)
Her plan is to get the bully leader thrown in jail, while the rest gets scarred for life or death. To do that, she sets up the place where the bullies are likely to assault her. Determining time and aftermath, she'll know it will go well. She makes sure that Aizawa couldn't interfere with her plan, hence sets up a trap for him (gets locked in the room or something). Aizawa wouldn't know about it and thought she's finally coming out of her shell.
The bullied girl brings out a self-defense weapon (the knife~fu). Girls just snicker and attempts to hold her down. Bullied girl manages to injures the leader and leader gets angry. They both have a confrontation, and bullied girl dies. Murdered by the leader, the girls panicked and get rid of the murder weapon. They assumed they would be safe...
Unfortunately... Just the right timing, Aizawa appears. With his 🎤 tie and trusty phone, records the crucial evidence. The bullied girl somehow predicted this.
Someone sends out an anonymous letter to each of them, blackmailing them that they know their secret. The girls start to get paranoid and eventually goes down one after another. The leader starts freaking out and seeks for Aizawa, hoping that he'll help her. Aiwaza, with a fake smile, reassures her. He had sent evidence to Suzuki prior to the girls' demise.
Suzuki, angered by his daughter's murder, sets out to revenge. He wants to give his daughter one last gift, sharing the pain that she had suffered to the criminals. He starts taking them down, except the leader. He threatens her that he'll kill her family and makes sure her life will be hell, if she doesn't do what he wants. He wants her to reveal the truth on live and kill herself on set.
She agrees, and attempts to do that... Then the police come and restrain her. Suzuki gets frustrated and gets arrested by the police for the murders. Both of them goes to jail. The leader gets PTSD after that, goes into hysteric screams. All goes well according to Aizawa's plan.
Aizawa, fully satisfied with his revenge, now wonders if he should have save that girl. Then shit happens, a student gets bullied by another group of bullies. Aizawa smiles, signifying his scheme has been put into motion once again.
In other words, he's going to repeat the same shit. Sends evidence to the father/mother -> parent kills the bullies -> have both the leader and parent arrested.
That is... If the victim doesn't attempt to suicide, Aizawa will "push" him to do so. Or.... He could manipulate the evidence against the leader to give him a solid motive to murder the victim.
The end.