Bonnie is Elena's best friend.
She used to joke she was psychic but soon discovers that having ancestors from Salem means much more than just that. She seeks help from her grandmother, who claims that she is a real psychic herself, a witch. Among her talents are pyrokinesis (she can set things on fire with her mind), clairvoyance (she has visions when she touches some people), manipulating water.
Katerina Graham - the actress portraying the character - describes Bonnie like this:
Bonnie is very sweet, loyal, selfless, goodhearted best friend. I don't know if you ever had that best friend that you grew up with that was always there for you, ride or die. Bonnie is that. She's very intuitive. She can vibe out certain things. She's innocent and sweet which I really love about her. She has had this sort of texture to her that's very clean and pure which I think is obviously a great platform to be a psychic. I mean who expect little Bonnie Bennett to torch a car. I love that. I love her vibe. Her energy is just so sweet and love and she's just a great friend.