Hogwarts is my home.
Voldemort himself created his worst enemy, just as tyrants everywhere do! Have you any idea how much tyrants fear the people they oppress? All of them realize that, one day, amongst their many victims, there is sure to be one who rises against them and strikes back!
Many years before, she had read, and recognized as true, the words of W. B. Yeats: 'A Pity beyond all telling is hit at the heart of love'. She had smiled over the poem, and stroked the page, because she had known both that she loved Colin, and that compassion formed a huge part of her love.
At this rate, we'll be the only ones left, Ron told Harry and Hermione. Us, Malfoy, Crabbe, and Goyle. What a jolly holiday it's going to be.
Brains like that, you could be a Death Eater, son.
Of course it is happening inside your head, Harry, but why on earth should that mean that it is not real?