My obsessions have always been people focused. From memorising the food people ate, being fixated at the sight of girl's hair, dolls, and then an all consuming interest in the actress Kate Winslet and child development.
From my teen years, and even to some extent in my childhood, I have a lived a vicarious existence where I live through other people and have no self-concept of my own. I sometimes fall in love with certain individuals and want to emulate them, to dress like them, and to do the same things as them. I don't usually share these obsessions with others for fear that they will misinterpret my obsession, but I understand boundaries and would never stalk the person - although I will obsessively research them and try and find out about them.
Does anyone else have people based obsessions? The Asperger stereotype emphasises an obsession with gadgets or objects, but my obsessions have always been people based, or about human systems like the body.