He had withdrawn to his office, since with no potion to watch over at the moment, pauses of concentration were legit and long overdue. Hermione had to slow down from her usual half-walking, half-running down the stairs, and stop at the bottom of them to catch breath. He might have heard her before she knocked.
"Miss Granger."
No way to tell his mood from such a short acknowledgment.
"P'sor", she forced air through the collar, "If y' c'd -"
"Sit first. I do not wish having to explain to Professor McGonagall how a student suffocated in my office."
That was her teacher talking, distant and strict. He had kept the two chairs at the crimson, if no flames crackled merrily in the fireplace, leaving the room dimly lit by a chandelier. She did as she was told.
"I am certain Mr Potter must have welcomed the opportunity to get into your robes."
"Tried."
"With your permission, I hope."
"Y's."
"Mr Weasley as well, then, for sure."
The still position allowed her to breath deeper. "Professor", she squeezed, "They tried, but couldn't -"
"Loosen you up?" He had not taken the chair in front of her, but kept staring, hand reached into the pocket of his robes, clenching his wand, no doubt. "Your head of house must be rather busy these days, if she can't make time to prevent you from getting strangled by your uniform."
"Didn't g'to her."
"Then you shouldn't have come to me instead."
"Why?"
"It's not my job to peel you from your uniform."
"This's 'rk m'gic."
"No, Miss Granger, it's not", he still denied her ease. "This is a garden-variety bridle reins charm."
"W'y loos'n 'his -", she had raised her voice, and regretted it at once, for blowing out more air than absolutely necessary made her cough hard.
"Stop arguing." He never let his wand go while seating himself after all, and watched her closely while she regained a speaking capability.
"Relashio", he made a predictable attempt, pointing his wand to the tie.
She resisted the urge to tell him about Harry and Ron's previous attempts.
"Hm. Finite incantatem."
The charm earned him the same result.
"Let's see", he mused, "Magia revelio."
Nothing happened.
"It seems", he slowly said, "That this tie must indeed be opened by hand."
"I'd lik' t'be 'le t'reathe 'gain", she croaked, temper definitely rising.
He put his wand to his pocket and pulled his sleeves back. "May I?"
"Ys", she repeated impatiently.
He reached for the knot. She had half expected him to touch, position, maybe tear it and tell her the tie had to be cut to release her neck from its grasp, but with gentle hands, he widened the collar first, then started to untie the knot.
"Anyway, what did you do that someone felt they had to put you in tight reins?"
"Wore them not at all", Hermione answered, inhaling deeply, as if for the first time ever.
"So how come someone made you wear -", he pulled it from her neck smoothly, "those?" He started to coil the slim cloth up to a role.
"Umbridge", she replied flatly, as if still short for air. Her collar still felt rather tight, but without the tie, she felt like she had slipped from a petard.
"I recall you seeing with an unusual choice in clothing this morning myself."
"Unusual in what way?"
"Unusual for you."
"I never wear this tie unless I have to." She had not omitted the 'Professor' on purpose, but noted that he had not told her off for it.
"Yes, but you were definitely … Loosened up."
"The first two buttons – everyone does that", she waved away his observation.
"Everyone but you." No 'Miss Granger' here, either.
They had not been this close for quite a while, with no kettle between them, none of them acting, none of them bleeding, and alone with each other.
"Suits you", he nodded to the tightly closed blouse.
"Me and my over-developed rationality – be frank."
"I was under the impression that your rationality has ceded to dominate your mind." Still, no formal address. "Do you agree?"
"So you still think of it as over-developed."
He hardly suppressed a smile. "Women -", he replied slowly, "seldom are as rational as you … Hermione."
Hearing him whisper her first name made her shiver like the scent of santal and a lonely lake beneath full moon he wore on that broad chest under that cloak.
"So since I've grown into woman", she said, "Loosening up seems pretty appropriate."
If she was not mistaken, his gaze swept to her lips before resting on her nose.
"I probably won't be able to open this collar, too", she whispered.
"Probably."
"Would you -?"
"On one condition." He unrolled the tie again. "Do you trust me, Hermione?"
"We're past that. Or else I would have left minutes ago", she repeated his words to him.
"There's no way I'll allow you into my mind right now." In a move slow enough she could have stopped him any time, he raised the band to her face, placed it on her eyes and tied it neatly behind her head. Two fingertips stroke her neck, as his hands found their way onto her shoulders. She was short for breath again.
"May I?"
"Yes."
He swept over her collarbones, heels of his hands first, then four fingers separately. The two thenars never broke contact while he opened the topmost button. She felt them tremble for an instant as he proceeded to the second one. Resting one hand on her shoulder again, he pulled the ribbon of the blindfold. "Here", he handed her the tie. "No more reins." His hand took the detour over her upper arm, wrapping her elbow, caressing her wrist, then rested in her hand.
"I'd like you to leave now."
"For the same reason you won't allow me into your mind", she replied. It was not a question.
"The very same."
She withdrew her hand, and respected his wish by not looking at him while rising from the chair. "May I come back?"
"Of course", he said, gaze fixed on his knees, hands clenched together in his lap. "Always."
"Thank you … Severus."
"Please leave, Miss Granger", he withdrew again, "Before your friends worry too much."