Hermione walked through the corridor with her spine stiff and her robes brushing against the stone walls. The stone was damp from the autumn rain, and the chill of the castle seeped through the soles of her shoes. She did not look back to see if Harry was following her; she knew he was. He had a way of walking that was heavy and deliberate, a sound that announced his presence without him ever needing to speak. The corridor was empty, save for the occasional suit of armour that stood like a silent sentry near the staircases.
"You are doing that thing again," she said, her voice echoing against the high ceiling. She did not stop walking, forcing him to match her brisk pace. "The thing where you stare at my hands as if they are some sort of arcane text that you cannot quite decipher."
"I am not staring," Harry replied, though his voice was thick with a sort of tired amusement. "I am observing."
"Observing is for scientists and people who are actually paying attention to the subject matter," she snapped, turning a corner sharply. "If you are looking at my hands, you are not looking at the wand. If you are not looking at the wand, you are not learning the nuances of the wrist movement. It is a basic failure of focus, Potter."
He caught up to her, his shoulder nearly brushing hers as they navigated a narrow bend. "Maybe the wand is just a distraction."
"A distraction? It is the entire point of the lesson!" Hermione stopped abruptly, turning to face him. She felt the heat of annoyance rising in her cheeks, a sensation that always seemed to accompany her most spirited debates with him. "You cannot master the subtle charms if your eyes are wandering. You are supposed to be tracking the tip, the movement, the intent. Instead, you are looking at my knuckles."
"They are very expressive knuckles," he said, a small, infurious smirk tugging at the corner of his mouth.
"They are not expressive. They are hands. They are tools for magic, not a theatrical performance." She crossed her arms over her chest, trying to regain her composure. "You are being ridiculous. It is a fundamental lack of discipline."
He stepped closer, encroaching on her personal space with a familiarity that felt new and uncomfortably potent. "Is it discipline? Or is it just that you are very loud when you are frustrated?"
"I am not loud, I am emphatic," she corrected him, her eyes narrowing. "There is a difference between being loud and being clear. You, on the other hand, are being deliberately obtuse."
"I think you're just annoyed because I'm not looking where you told me to look," he said. He took another step, his boots clicking on the floor. "You spend so much time explaining the theory, and then you want the practical application, but you keep getting distracted by your own irritation."
"My irritation is a logical response to your lack of focus," Hermione said, her voice rising an octave. She began to walk again, her pace even faster now. "It is an ordered response. When one performs a task correctly, one receives praise. When one fails to follow the most basic instruction of eye contact, one receives a critique. It is a very simple sequence of events."
"You’re doing it again," he said, catching up to her side.
"Doing what?"
"The thing where you start a lecture because you're actually just mad about something else."
"I am not mad about something else! I am mad about the wand! And the fact that you are a mediocre student when you should be an exceptional one!" She turned to him, her eyes flashing. "It is infuriating. You have all the talent in the world, but you spend the entire time looking at my skin instead of the magic."
"I'm not looking at your skin," he lied, and she knew he was lying because his eyes dropped to her wrist for a fraction of a second.
"You are. You are absolutely looking at my hands. It is a symptom of a shallow intellect, Potter. You see the flash of movement and you lose the thread of the spell. It is a common error in people who lack patience."
He laughed, a short, dry sound that made her want to hit him and kiss him all at once. "A shallow intellect. That's a new one. Is that the part where you list my many failings?"
"It is a list of observations," she said, her chin lifting. "And it is a very long list. You are arrogant, you are distractible, you are hopelessly stubborn, and you are currently failing to demonstrate even the most basic level of ocular control. You are a chaos of unrefined potential."
"Is that all?" he asked, his voice dropping an octave.
"No, it isn't all. You are also incredibly frustrating when you pretend to be oblivious. You act as though you don't see the way my fingers twitch when the spell is nearly complete. You act as though you aren't watching the way the ink stains my fingertips when we are sitting at the table in the library. You are a very poor observer of detail, despite what you think."
"I see plenty of detail, Hermione," he said, using her name with a deliberate softness that made her breath hitch.
She cleared her throat, refusing to let the sensation linger. "Don't do that. Don't use my name to soften the blow of your incompetence. It is a cheap tactic. It is a way to bypass the actual argument."
"We aren't even having an argument. You're just insulting me."
"It is a structured critique!" She waved her hand vaguely in the air, her temper flaring. "A critique is a structured, logical, and necessary part of the learning process. If you want to be a master of charms, you have to be able to take the criticism. You can't just stand there looking at my hands and acting as if you've understood the lesson."
"Maybe I have understood the lesson," he said, his eyes meeting hers. "Maybe the lesson isn't just about the wand."
"Then what is it about?" She challenged him, her heart beating a little faster against her ribs. "If it isn't about the wand, then what are you actually studying?"
"I'm studying you," he said, his voice steady.
"That is a terrible answer," she snapped, though she felt a strange warmth spreading through her chest. "That is a completely unscientific, non-academic answer. You are supposed to be studying the wand. You are supposed to be watching the movement of the wood and the light. You are not supposed to be studying my hands or my face or the way my hair falls."
"It's a very interesting study," he murmured, stepping closer until the heat from his body was palpable.
"It's a distraction," she insisted, her voice slightly less certain than it had been a moment ago. "It is a detour from the actual work. If you keep looking at me instead of the wand, you will never master the subtle nuances of the charm. You will always be one step behind because you are too busy being enamored with the instructor."
"Who said anything about being enamored?" he asked, his eyes scanning her face with a precision that made her feel exposed.
"You didn't have to say it. Your eyes say it. Your lack of focus says it. Your entire presence says it." She took a breath, trying to pull herself back into her usual, composed self. "It is a lack of discipline. A total lack of professional decorum."
He watched her for a moment, his expression unreadable in the dim light of the corridor. He looked as though he wanted to say something else, something that would break her composure entirely, but he held it back. Instead, he just watched her, his gaze heavy and constant.
"You're doing it again," he said