Gideon Planish by Sinclair Lewis

For a gentleman professor in Kinnikinick College to look upon a maiden student as a human being was poorly thought of, and to meet her over a dish of marshmallow, ground nuts, caramel and two kinds of ice cream was as dangerous morally as it was dietetically. Now that he had once run that danger, he did not dare try to see her except across the footlights in his Rhetoric class.

She was, by alphabetical arrangement, half-way back in the room now, and when he started his second lecture, he looked about for her flutteringly, and was reassured by her smile that said, "Yes, here I am!" Through his discourse, her attention told him that he was good--but afterward she treacherously slipped away with the rest of the class, and he was in a terror of uncertain love.