Square used as slang may mean many things when referring to a person or in common language.

The meaning of the word refers to a like-minded person.

Often it refers to a person with a short attention span.

It also refers to such a person under Scottish law.

Put your hand up if you think "she" can only ever refer to a specific female person.

Originally, it was simply used to refer to a black person.

Personal pronouns refer to a person: I go to school.

If one is to refer to a person with a single name he/she will always use the person's given name.