I keep having dreams about.....?

demons,occult,ect.I fell asleep today (as I do very often) and I had a dream that a woman was in an abusive relationship,and she said when nobody else was around except for her and her boyfriend,he was a monster.like he actually grew claws and hurt her.in my dream he was either possessed by a demon or was one in human form.he was merciless and enjoyed tormenting & trapping her (she wasn't really allowed out much).the number 666 kept appearing in my dream.sometimes that was all I would see,just the number in my head.nothing else.why do I keep dreaming about things like this??Im not a satanist or anything like that,I dont enjoy this