Petunia Dursley

Petunia Dursley (née Evans) is Harry Potter's aunt. (Harry's mother, Lily, was Petunia's sister.) Harry is left at the home of the Dursleys after the murder of his mother and father. She is married to Vernon Dursley. She is thin, blond (in the movie she is portrayed as dark haired) and has "nearly twice the usual amount of neck" (PS) She is very nosy and often spends her time spying on her neighbours.

Petunia's parents were Muggles who were, according to Petunia, delighted when their daughter Lily was invited to attend Hogwarts. Petunia appears to have deeply resented her sister's magical talents, and referred to her sister as a "freak". As if to emphasize the distinctions between herself and Lily's oddities, Petunia charts for herself a life of utter banality in a three-bedroom semi-detached home in Little Whinging, Surrey. Into this ordered suburban life Dumbledore, Headmaster of Hogwarts, drops the infant Harry. Petunia and Vernon treat Harry very much as a second-class member of the family, consigning him for most of his childhood to the cupboard under the stairs. They tell him that his parents have been killed in a car accident and give him no clue that his parents were wizards. Perhaps most importantly, Harry is given no whisper of affection or nurturing, so that his childhood passes entirely empty of any kind of love.

In stark contrast to their neglect of Harry, the Dursleys indulge their own son Dudley with food, gifts and coddling attention, setting Dudley on the path to becoming an obese self-absorbed bully.

When Harry is brought into contact with the wizarding world, Dumbledore is appalled at the mistreatment that Harry has endured at the hands of the Dursleys, but as there is a powerful enchantment protecting Harry so long as he has a home with his aunt and uncle, he is resigned to requiring Harry to return to the Dursleys between school terms. Petunia grudgingly puts up with Harry's presence in her home, although it is not entirely clear whether she does so under some obscure threat from Dumbledore or because of a faint glimmer of family loyalty. In Harry Potter and the Order of the Phoenix, when Vernon Dursley is on the verge of throwing Harry from the house after the Dursleys discover that Harry's presence has attracted Dementors to their suburban neighbourhood, Petunia ultimately refuses to allow Harry to be turned out, cloaking her decision by alluding to the awkward questions that will be asked by the neighbours if Harry suddenly disappears.

Attitude towards magic, wizards, and witches
Petunia is frequently heard referring to witches and wizards as "freaks;" as her sister Lily left for Hogwarts the first time she refers to it as a place for "weirdos," a place where they may be "separated from normal people" for the safety of the latter.

Petunia's attitudes toward the wizarding world most probably stem from her deep desire to attend Hogwarts, only to be rejected. After Lily's invitation to attend, Petunia wrote headmaster Dumbledore, asking that she also be permitted to study there. Dumbledore's kind rejection seems to have resulted in a severe case of sour grapes towards Hogwarts and the wizarding world in general.