I'm gonna fix my ex bf tonight

So here's the story. Tell me what to do before I do anything stupid. My ex only got with me for my pussy and at the time I didn't know that because I was being a dumb bitch. One day he had the nerve to do Dd accuracy test and he came out to be 100% slime. Long story short I dumped his ass. But ever since he was saying that he's gonna rape me and i don't believe him but I do think he can do it so i've been staying on Reddit. I decided to fix him tonight and i'm trying to convince him to be good but it's not working. So he came over and i'm gonna tell him to do the test again and if he is slime again then I am gonna try to get him to be good and if that doesn't work then i'm gonna kill him. So now I need some advice how do I kill him? Please send me some advice before he kills me first!