I Can Enter Other People's Dreams

I can enter other people's dreams. I have entered the dreams of Cthulhu lovers, and witnessed the true appearance of the Lord in Yellow at the end of the dream. I have also entered the dreams of children who like Ultraman, watching Ultraman fight monsters, and some personal original dreams. I have witnessed many miracles of human imagination. But now, I am confused, I am not sure whether I am in reality or a dream. If this is a dream, why does a perpetual motion machine exist? If this is reality, then why... Ultraman is fighting the Lord in Yellow? ! !