Is my boyfriend a serial killer?

I've been living with him for about 2 years and he's perfectly fine. He never said anything bad about anyone or shown any signs of being aggressive. Today when we were having a shower he asked me if I was a 'missing' person? he also mentioned that he was online shopping and saw Martin bitten as a cart in my shopping list. I frankly don't understand who is Martin bitten but he told me that he is a serial killer. I was shocked and asked him if he was Martin bitten and he said this is his real name. Is it a coincidence? I don't want to be the next victim.