'We'll call it Hogwarts, after the village.' Rowena stood on the flat-topped hill, gazing across the rippling lake that was framed on one side by deep, dense forest. Mountains surrounded the valley, casting strange shadows across the glen.

After that, not much was to be done. With a flick of her wand, Helga Hufflepuff had erected a splendid castle. It was a building unheard of, grey stone with turrets. The four watched in awe as it built itself in seconds.

'There'll still be the insides,' she said anxiously, but Salazar just put his arm around her. She wriggled out of his grip, disgusted.

'It's perfect,' he said, a genuine smile on his face. 'But does it have dungeons?'

'I prefer the term "basement" better,' Rowena said tartly. 'And yes. There are now.' She swished her wand and the ground began to bubble. A small island rose in the lake.

'What was that?' Gryffindor asked.

'I've hollowed out the underneath of the castle,' she replied. 'The earth has all pushed along and gone up under the lake.'

'The lake . . .' Slytherin looked across it.

'Yes. Not all of the dungeon will be under the castle,' she decided. 'Some will be under the lake and grounds. And there will be passages; ways of escape.'

'I hate to sound impatient,' Godric interrupted. 'What's the inside like? This is just the bare bones!'

'I'm getting onto that. First we need doors, and windows. Also, who shall be responsible for what part of the castle? I'll have that tower, and that round one,' Rowena said dreamily. 'And the east and south wings. One can be a healing hall.'

'The dungeons,' Salazar said, a glint in his eyes. 'I like the underground. And . . . I think that those secret passages are work for me.'

'Then I shall have the other main towers, and the west and north,' Godric said firmly.

'I guess whatever's left is for me,' Helga huffed. 'I'll take the bottom floor, upper west basements and kitchens.'

It was barely a month later that the school was complete. Helga stood back and admired her work, not noticing Slytherin behind her. He flew a tiny enchanted bird onto her shoulder, where it perched and cheeped in her ear.

'What's that?' She spun round.

'I was saying hello,' he smirked. He looked up and down her body from where he was leaning against a stone pillar. She had a beautiful figure; a little short, but that was made up for by voluptuous curves.

'Ah. Well, hello,' she smiled hesitantly. Salazar held out his hand to reveal a tiny apple.

'I thought you might be hungry,' he explained, a little too kindly. Helga looked into his eyes suspiciously.

'What have you done to it?' she asked.

'Damn,' Salazar muttered. 'You're cleverer than you look.'

'I'm sorry?' she asked furiously. 'Was that an insult?'

'Maybe,' Salazar said, his lip curling upwards.

'You! What happened to the powerful sorcerer, the wise hermit?' Helga asked.

Salazar didn't tell her that over the weeks he'd been watching her. The way that her dress moved down her front when she bent over to charm a small crack together, her chuckling laugh; all registered in Salazar's mind so that when the time came, he could -

'He was left in my cave,' he said cunningly. In a way, this was true. Salazar had abandoned that side of him when he'd come to Hogsmeade.

'I hope your vile snake was left with him,' she muttered.

As if on cue, a low hiss could be heard from the corner. 'Hello, Rip.' The snake slid up and over Helga's newly polished floors, and up Salazar's arm and around his neck. He stroked the snake and left without saying goodbye.

As soon as he had gone, Helga sat on one of the wooden benches that populated her latest teaching-room. The fluttering in her stomach that had filled it when Salazar had put his arm round her was gone, but a ghost of it remained. She shivered, remembering the cold touch of his eyes on her chest. His eyes hadn't touched her, but she felt like they had.

Helga had loved many, it was no secret. But none were powerful sorcerers.

The hardest part of Hogwarts' creation, Rowena decided, had to have been the stairs.

She had wanted every day to be a challenge for her students so each staircase was enchanted. It had taken more work than the furnishing phase of her section for good reason - every so often, the staircase would suddenly move to join up with another door.

'Why, Rowena?' Salazar had sneered at first; well, he sneered at everything; then he'd wandered off to find Helga. He'd even said that was what he was doing, as if he hoped to make her jealous.

Poor, innocent Helga! Rowena could tell Salazar was up to something, her diadem was practically quivering. So she decided to confront Godric.

'You know,' she said carefully, as they ate their small meal of grouse and butterbeer, 'Salazar has acquired an interest in Helga recently. And I don't think he means the best for her.'

'I will protect her honour,' Godric said darkly. 'But it pains me to cross a friend.'

'I understand,' Rowena said sadly. Still, the paladin-nature of Gryffindor would help, she was certain of it.

But she herself still had an underlying fear for Helga. She didn't know Salazar as well as she thought she did; Rowena knew all his secrets, all his lies. Shaken, she continued to sip her butterbeer. Helga could defend herself; at least, Godric would protect her.

It was a cold day, the kind you get just as spring approaches in Scotland, and Rowena wrapped herself up tightly against the wind as she headed through the misty grounds. She loved the autumn, winter and early spring. They were so clean cut and pure, unlike hazy summer with its pollens and beaming sun. She liked the early darkness and short daylight, giving her more time to practise stranger spells - and this made her rather like Salazar. In the past they had consorted . . . Rowena was disgusted to remember the foolishness of her younger years. Now that she had the wisdom that being older gave her, and her diadem to help her, she saw he was a snake and would slither into unexpected places if she did not contain him.