AITA for not confronting my sister’s ex boyfriend who is my coworker too.

My sister and I work in the same company. She works as a business manager and I work as an IT specialist. I have a good relationship with my colleagues but there is one guy who is kind of annoying. He’s too nice and caring to me and I always felt like he’s doing it to get close to me. I tried to ignore but once he even told that he’s going to be my boyfriend one day. I found it creepy. I didn’t want to make him angry or make a scene so I kept it to myself. It was until my sister broke down crying in my office.<br><br>She told me that her boyfriend of four years cheated. They were in a long distance relationship and he was from another country. He tried to make her send nudes and she trusted him and sent. He blackmailed her to send money. He also asked for pics of her in the office. I suggested to report to the management but she was afraid she might lose her job. So I decided to handle this myself. <br><br>I decided to pretend I’m doing an investigation. I got the access to all the employee emails. I found out that the guy was my sister’s ex. I was so mad. The emails were full of nudes. He was sending to himself the nudes. I took my laptop and went to his office and I showed him the emails and told him I’m going to report to the management and I might involve the police. He was begging. At that moment I got angry. I might have also felt betrayed he was into my sister too but I yelled at him for a while. I told him he’s a sick creep and I’m not going to do anything because I might involve my sister but he needs to delete everything and never talk to her. He was crying and begging so I left him. I felt so sick and angry. <br><br>I told my sister what happened and she broke down crying. She told me she wanted to report to the management and the police but she was afraid to lose her job. She confessed everything to her superiors and they were cool. They told her to report to the police. <br><br>The police told us that the guy was already on their list and the company fired him. He was also fired from his previous job for sexual misconduct. <br><br>The thing is my family is kind of blaming me for not reporting to the management or the police. They think I overreacted and made a scene there. They think I’m immature. AITA?