Harry Potter and the Order of the Phoenix2007

[Snape has just witnessed Harry's memory of seeing his parents in the Mirror of Erised.]

Snape:
Feeling sentimental?

Harry:
That's private.

Snape:
Not to me. And not to the Dark Lord if you don't improve. Every memory he has access to is a weapon he can use against you. You won't last two seconds if he invades your mind. You're just like your father. Lazy, arrogant.

Harry:
Don't say a word against my father.

Snape:
Weak!

Harry:
I'm not weak!

Snape:
Then prove it! Control your emotions! Discipline your mind! Legilimens!

[Series of flashbacks, including a touching moment between Harry and Sirius.]

Harry (In Memory):
Sirius.

Snape:
I may vomit.

Harry:
Stop it!

Snape:
Is that what you call control?

Harry:
[heavy panting] We've been at it for hours. If I could just rest!

Snape:
The Dark Lord isn't resting. You and Black, you're two of a kind, sentimental children forever whining about how bitterly unfair your lives have been. Well, it may have escaped your notice, but life isn't fair. Your blessed father knew that, in fact he frequently saw to it!

Harry:
My father was a great man!

Snape:
Your father was a swine. Legilimens!

Harry:
Protego!