At the Edges
At first, she thinks it's a trick of the mind: wishful thinking or curse residuum. After all, isn't it impossible that Severus Snape would be paying any attention to her whatsoever? He's never liked her as a person, and now the war's over, he's his pick of witches. But time passes, she sees him at multiple functions and locations, and she'd swear that every time, she catches him looking at her from the corner of his eye.
Perhaps she looks prettier— or more anonymous —in his peripheral vision.
Because he'd certainly never look at Hermione Granger with anything like desire.