Dear Professor Snape,
I believe you wash your hair. How often do you it though? It's is greasy you know. Maybe you a heavy duty shampoo?
Sincerely,
Just Trying to Help
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Dear 'Just Trying to Help',
I doubt you're trying to help, and whether or not it looks greasy does not matter to me; I'm a professor not an owner of some muggle hairdressers!
-Professor Snape
He looked online for different shampoo later on… Don't tell him I told you!
