"It wasn't anything romantic, but we'd be in class and he'd say things like - "Oh, Hermione wouldn't brew the potion like that, she'd do this instead, which is better," or "Hermione says that bit of History of magic is wrong, because it's mer-people sourced, and they can't write anything down on account of their webbed hands...'. Stuff like that. It was like you were always on his mind.