Legal side of /pol/ I'm in a predicament and asking for your help.

There's this fucking Romanian in my town and twice now he's gone into the shop where my sister worked and asked her for Oral, She works on her own most of the time and she's really shook up about it happening again. We've called the police and twice they've said they can't do anything until they find him and just overall been completely useless. I'm going to stake out near the shop tommorow and wait for him, If I kick the absolute shit out of him with a weapon what sort of sentence am I looking at? How about without a weapon? He's done this to other girls too so it has to fucking stop and if I have to go to jail for a few months to be the one who stops it so be it. What are my options?

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