It seems to me that Snape is being silly and honest at the same time, stumbling over how to express his thoughts — very much in the “So, my friend has this problem” vein, but with a twist. It’s kind of like the old riddle, “I have two coins in my pocket that add up to fifteen cents. One of them is not a nickel. What are they?”
“Not you” means “No, I’m not saying that I have a crush on you.”
However, he is talking about a boy who attends her Potions class, namely himself.
No, I’m pretty sure his “not you” is almost entirely literal; you seem to be missing the analogy. In the hypothetical he’s considering (“suppose that boy had helped you”), the situation of the boy with respect to her is analogous to the real situation of her with respect to Snape. Hence when he points out that she would probably consider him bothersome… well, you see. “Not you!” indicates that, though the analogy is present, that wasn’t what he was going for; he is simply considering a hypothetical about an actual boy, not making a jab at her by means of analogy.
(Or in short, JoshuaZ is right. Added: See also jaimeastorga2000′s comment.)
To explain the stumbling, keep in mind that he’s probably never kissed anyone before, ever. We understand this because he fell in love just on the cusp of puberty and carried the torch up until Harry disillusioned him in the wallway after saving Lesath. Felthorne doesn’t have the context we do to know the depth of the situation, but she realizes that she is his first kiss just before being obliviated, simply from the physical details.
It seems to me that Snape is being silly and honest at the same time, stumbling over how to express his thoughts — very much in the “So, my friend has this problem” vein, but with a twist. It’s kind of like the old riddle, “I have two coins in my pocket that add up to fifteen cents. One of them is not a nickel. What are they?”
“Not you” means “No, I’m not saying that I have a crush on you.”
However, he is talking about a boy who attends her Potions class, namely himself.
No, I’m pretty sure his “not you” is almost entirely literal; you seem to be missing the analogy. In the hypothetical he’s considering (“suppose that boy had helped you”), the situation of the boy with respect to her is analogous to the real situation of her with respect to Snape. Hence when he points out that she would probably consider him bothersome… well, you see. “Not you!” indicates that, though the analogy is present, that wasn’t what he was going for; he is simply considering a hypothetical about an actual boy, not making a jab at her by means of analogy.
(Or in short, JoshuaZ is right. Added: See also jaimeastorga2000′s comment.)
To explain the stumbling, keep in mind that he’s probably never kissed anyone before, ever. We understand this because he fell in love just on the cusp of puberty and carried the torch up until Harry disillusioned him in the wallway after saving Lesath. Felthorne doesn’t have the context we do to know the depth of the situation, but she realizes that she is his first kiss just before being obliviated, simply from the physical details.