He was called into the office two weeks before Yule and with a pounding heart he made his way through the warren of corridors, past the library tower and up the staircase of the staff tower.

His mother already sat opposite the headmaster and at her side...

'Hermione!' He breathed. He barely managed to open his arms before she had thrown herself into his chest. Her arms, strong and lithe from sword fighting, wrapped around his chest and he brought his own down over her shoulders. She was wearing that grey Fenrir skin cloak that made her look terrifying and she had Mordred's sword belted at her hip.

'What's going on?' He asked after a moment, glancing at his mother over Hermione's shoulder and realising with a start that he was now a fair bit taller than her.

'The Coven are going to assist in Russia.' Hermione mumbled into his chest. Concern chilled his chest.

'I didn't realise it was that bad.'

'Nobody does. That's the point.' His mother said shortly. 'Hermione will be attending lessons with you until I return.'

'Lady Grindelwald.' The headmaster huffed. 'I really must protest, your ward is only twelve... she should be in her second year...' He quailed under the glare both witches levelled at him.

'You'll find Hermione's abilities equal to all your third year students. Anything where she falls behind, my son will find the time to bring her up to scratch.' That terrifying glare was fixed on him to let him know that he had no choice in the matter and that he would be held responsible if Hermione should fail to meet her standards.

'She can take rituals as an elective, runes too. She'll like those.' He decided, grinning down at his suddenly short sister.

'And magical theory.' Hermione added. 'That sounds fascinating.'

The headmaster pursed his lips unhappily, but eventually nodded and agreed to pass on that information to the third year teachers.

Then, his mother turned to him and held out a ring. His heart stopped in his chest.

'I'm naming you as Locum Patriarch.' She informed him. He took the ring from her hand, feeling like it weighed more than it should for such a small piece of silver. The deep blue sapphire face glittered with the familiar cockatrice and dragon, exquisitely detailed as they fought.

'Give the heir ring to Hermione - I believe Berg will more than understand.' She instructed, 'Your sister has already held the position, and will be able to assist with the duties.'

He pulled the familiar ring off his finger; it was smaller and there was no crown on the shield the two beasts fought over. Immediately, he replaced it with the head's ring and passed the heir's ring to Hermione. She slipped it onto her little finger - she wore a lot of rings now, he noticed. She had an unusual band on her ring finger that looked an awful lot like a coven band, which he always assumed was something to do with the sect as the design was very similar to the crown she'd once had. Her Gorlois seal took up her pointer finger, so she slipped the Grindelwald heir's ring onto her little finger. It shrunk immediately to fit.

'Excellent. I will take my leave. Do me proud.' His mother stood and he bowed deeply as she disappeared out of the door, leaving them alone with the headmaster who sneered at them.

'I warn you now - one hint of you being behind and I shall have you with the second years faster than you can blink.' The headmaster warned. Hermione bared her teeth at him.

'You needn't worry. Let's go, Gellert.'

She strode out of the room, grey cloak brushing the floor as he hurried after her.

'Mother got you a uniform, right?' He checked quickly.

'Obviously.' She drawled, 'the only thing I'm missing is a staff because the Wood brothers have already left for Russia.'

'Mine will be too big for you.' He observed, subtly taking the lead to show her where to go.

'I'll use the sword.' She shrugged and he sighed, hoping that his duelling teacher wouldn't mind. Of course, given Hermione's duelling ability she would probably be his favourite within minutes.

'Here. I'm on the third floor.' Gellert paused at the bottom of the stairs. 'I guess you'll be taking Petrovna's bed? It's on the fourth floor. Do you want to change before lessons? We've got duelling now - they've probably already started.'

'No. I wouldn't want to fall behind...' She trailed off, blinking innocently. He laughed, taking a right instead and jogging out into the courtyard. The students were just finishing up the gruelling fitness regime that started every lesson with Herr Hor. As soon as they entered, every eye fixed on them.

'Grindelwald, you're late.' Hor growled in his deep voice.

'I had to see the headmaster, Herr. My sister will be joining us.' He stepped aside, allowing Hermione out into the icy courtyard. Immediately, whispers swept through the students and the teacher frowned irritably.

'She is a second year.' He huffed. 'Take her to Herbology.'

'Mother insisted that she take classes with me.' Gellert pushed. 'The headmaster agreed.'

'I shall be the judge. I will not allow an inexperienced dueller to endanger everyone.' Herr Hor glanced down the line of students, then his lips curved cruelly.

'Nowak. Step forwards.' He instructed. Jakub Nowak obeyed sharply, a grin as vicious as Hor's on his face. 'You shall duel Miss Grindelwald. Should she hold out for perhaps... thirty seconds, I shall permit her to remain in my class.'

Nowak was easily the best of the progressionists at duelling, and because of the ideological differences between them it was almost guaranteed that he wouldn't go easy on the youngest Grindelwald.

'It would be my pleasure.' Hermione purred. 'Perhaps you could hold my cloak, Gellert.'

He grinned in reply and took the heavy, luxurious fur as she passed it to him. This was far from a fair match, and not in the way that both Nowak and Hor were expecting. Nowak would be the one pressed to last thirty seconds.

She strode across the courtyard, stepping over the warded line confidently and made her way to the centre where Nowak was already waiting.

'Bow.' Hor ordered. His cruel expression had faded slightly at the absolute confidence the two siblings showed. Nowak bowed whilst Hermione curtsied deeply, her silk dress pooling across the courtyard. She certainly wasn't appropriately attired for duelling and Gellert could see several of the students muttering uncomfortably. He could see why; facing Nowak without her fur cloak, Hermione looked very small.

With a clack of high heels, Hermione spun and paced neatly to the opposite end of the duelling arena. Nowak did the same, then they both turned back to one another and drew their wands.

Nowak sneered aggressively.

Hermione smiled serenely and Gellert could already feel the familiar warmth of her magic heating the air around him.

'Remember; no permanent harm, Nowak?'

'Yes, Herr Hor.' Nowak agreed.

'Miss Grindelwald?'

'Of course, Herr Hor.' His sister hummed.

'Three, two... one.' Herr Hor counted them in. The last word had barely left his lips when Nowak whipped his wand up and over. Fire arched from the end, lashing down to strike Hermione. She batted it aside with an easy shield charm, then cast three wandless, silent spells as Nowak. The older boy took one against a shield with an impact like a cannon, then dove sideways out of the way of the others.

He shot a tripping jinx from the ground, bellowing the incantation so loudly that Hermione had already sliced her wand in a counter before the spell had a chance to really take effect. Without pause, the slash arched upwards and plants burst up from between the cobbles, snarling into tangled briars before Nowak had a chance to climb up. He thrashed and sliced his way out with crimson cutting curses and was forced to take four of Hermione's heavy-hitting jinxes straight on his shield. Nowak's expression had turned from glee to anger and began to cycle towards fear as Hermione set the remaining briars alight with a flick of her fingers. Nowak conjured water to put them out, and Hermione constricted the magic that saturated the air. The temperature plummeted well below freezing and several students cried out in surprise. The water Nowak had conjured froze, bonding his shoes firmly to the floor. He conjured fire, singing his own robes in a desperate attempt to free himself.

Casually, Hermione strolled across the frozen courtyard, unaffected by the arctic temperature she'd created. Nowak cast a whole volley of desperate charms but Hermione batted them away with practiced ease until she was within reach of the older boy. Like a muggle, Nowak swing at her with his fist and in a move that Mordred had almost certainly taught her, she swayed easily sideways, grabbed his fist as it flew past her ear and yanked - hard.

Unable to steady himself with his feet locked in the ice, Nowak teetered precariously before toppling forwards out of his shoes. Hermione's finger's twitched and his wand flew to her hand as her opponent reached out to catch himself.

Then, with a curtesy that was so deep it was almost mocking, she strode out of the arena to thunderous applause from the other students. Gellert fastened her cloak back around her shoulders with a grin.

'Warm it back up again! Not all of us are wearing cloaks.' Berg called from across the courtyard, looking as jubilant as Gellert felt. Hermione eased her hold on the magic quickly and the temperature eased back up far slower than it had cooled.

'Very impressive, Miss Grindelwald.' Herr Hor drawled, his deep-set eyes sparkling. Their duelling instructor hated incompetence and had little patience for those who did not take his subject seriously but he took delight in good duellists. Gellert had known he'd love Hermione once he got a look at what she could do. 'I should have known better than to misjudge you.'

'Oh, it's okay. I haven't duelled in a while. Lady Grindelwald has been very busy.'

Herr Hor hummed looking her up and down, then turned back to the rest of the class and ordered them to split into groups to practice combat transfiguration. As usual, he then promptly change all of the groups to split them up in ways less likely to end in disaster.

'You two!' He ordered, pointing at Gellert and Hermione. Then he hesitated. 'Inside the duelling arena, both of you. You've both got the ability to do some serious damage to any idiot who gets in your way.'

Around them, groups began waving their wands. Gellert obediently followed Hermione into the warded arena.

'We've got to cast a ward on each other.' Gellert told her firmly, 'it's the rules for this class. Watch me, then copy it for me?'

Hermione nodded and he waved his wand over her, recanting the short incantation. For a brief moment, silvery light flashed over her skin. She opened her eyes quickly and copied the spell, her warm magic caressing his skin.

'You start?' She offered. Gellert wasn't willing to pass up the offered advantage. Hermione was a better dueller than him, having received a year of intensive one-on-one tuition before her duel with Alice. Not to mention Mordred was a brutal fighter and she regularly trained with him over the holidays.

'Sure.' He drew his wand, eager for a chance to really throw himself into a duel.