Which aspects do you think makes a person unique?

A person can fake lot of things from emotions to how they live. However there is one aspect that even with trying hard can’t be faked and that is a person’s character, and this is one aspect that makes the person unique…………
We fall in love with person’s character and nit their body,
We trust someone based on their character and not their intelligence,
We become friends with someone based on their character and not their introvert or extrovert nature………..
Since we all form relations with someone based on their character ,then it will not be difficult to find what aspect makes a person unique?