Biography
Rita Skeeter is a secondary character of the Harry Potter series. A popular journalist, who has her own column in the Daily Prophet, Rita displays a fake concern and interest in people she thinks may bring her a scoop.
She turns up at Hogwarts during Harry's fourth year and she is in charge of writing up the articles presenting the champions competing in the Triwizard Tournament, but it soon becomes clear she is far more interested in Harry.
She manages to corner him in a broom closet and tries to get some kind of confession from him about being the Boy-Who-Lived. Harry is very talkative, but Rita doesn't mind. Her Quick Quotes Quill seems to be writing an interview of its own, and indeed, when the story is published, not one word is true.
Rita continues to snoop around and publishes several more articles, linking Harry with Hermione and portraying him more and more as a troubled teenager. Hermione looses her temper and swears to find out how Rita is coming up with her stories.
Hermione soon figures it out - Rita Skeeter is an unregistered Animagus and cna turn into a beetle, allowing her to spy on people without them noticing, and collect all the info she needs to write ground-breaking stories. Hermione captures her in a jar and forces her to never write a story again, threatening to reveal her illegal powers.
But even if Rita is no longer writing, she planted the seeds of a ministry encouraged round of 'Harry-bashing'. The Wizarding World seems to think he's demented and the Daily Prophet is constantly publishing crazy stories about him. As things get worse and worse, Hermione makes Rita write another article, a truthful one this time, and to her utter disgust, for The Quibbler.
Of being evil
I've often asked myself what house Rita would have been sorted into when she attended Hogwarts as a teenager. And without a doubt, only one house springs to mind. Slytherin.
Although Rita is not all evil in a 'I'm-going-to-kill-you/Avada-Kedavra' way, she is still evil. She deliberately chooses to lie and deceive to get what she wants. She will get her story. By All Means. Like a Slytherin.
Rita Skeeter is a more human evil in a way. She is not an all dark evil, take over the world villain, but she does a lot of harm, and shows no remorse, and only stops because she has no choice.