彼女is a third-person pronoun meaning she or her. In modern Japanese, it is also the standard word for girlfriend. When used as a pronoun, it can sometimes sound overly formal or Western-influenced; referring to people by name is often preferred.
That is how Fuguro works. It brings 彼女 back for review right before you forget it, each time a little later, until it sticks for good. You hear it spoken aloud, and you meet it again in stories you can already read. The first five levels are free.