I would be a bit scared to say who I am least like because I am sure to discover they represent a part of myself that I reject, or hate, or am ashamed of, or fear, or perhaps they are the person I most fear becoming, or the person I most want to become, but hide it even from myself.
It's possible that you could express that sort of thing by naming an opposite, but most relationships between people and ideas are not one-dimensional. They are not always subconscious and indirect, they are not always conscious and direct. Some people will name actual opposites, some will name a person as you have described, others will find someone with just the right combination to suit the complexities of their own mind. It is so important when analyzing people to not take a single-dimensional approach whether that approach is the most direct and brash possible or the most indirect and subtle possible. The principle of undermining the complexity of how people think and relate is the same.
The first man to raise a fist is the man who's run out of ideas. H.G. WELLS
The first principle is that you must not fool yourself, and you are the easiest person to fool. FEYNMAN If this is monkey pee, you're on your own.SCULLY