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Snape doesn't seem too intent on acknowledging your presence as you two walk along the grounds. You'd almost need to dump your bottle of pee on him to catch his attention, and maybe even then...
"So...." you start, wondering if you can spark a conversation and break the silence.
Nothing. You clear your throat and try again.
"Professor Snape, have you been teaching here very long?"
Nothing.
"Ayoooo. Snapeyyyyy. Can you hear meeeee" You wave your hands around as you speak.
Nothing. Well for god's sake...
"SNAPE. SNAPE. SEVERUS SNAPE. ARE YOU DEAF"
So that answers two questions; it can talk, and it can hear. You flush, a little embarrassed, and most of the rest of the walk is spent in silence.
