to Professor Snape:
I have been asked by Professor Lupin to assist him, so I must ask a favour of you. He is in need of some information on the uses of dragon-related ingredients in potion-making, for a portion of his Dragons Lecture. He is extremely busy preparing his lecture, due to the constraints of the upcoming full moon, so if I could stop by at your convenience to pick up that material it would be most helpful to him. Thank you.
~Sirius
~Sirius