I'm being targeted by a disgusting pervert. What should I do? Why don't you beg your big brothers to do something quickly?

You can call the police already. They caused you personal harassment, and the police will file a case.

Then, go home and point to your cousin's face and say that he is hurting people. If the other party kills you, he will also bear legal responsibility.

Finally, I really suggest you change the blacklisted mobile phone and make a phone call. I can't believe they have so much leisure to talk to you. If this is the case, the police will teach them how to behave.