'You deal with Snape's release papers. I'll collect him,' said Tonks, turning to where three great hooks supported the infamous portkeys to Azkaban. There remained two slender iron bands; the third absent, far to the North, on the prison's corresponding hook

'Auror Tonks . . .'

'You don't want to get in the way of an Auror doing her duty.' The clerk swallowed. 'Let me rephrase that.'

'No need.' The clerk stood, stiffly, out of the way. Whatever warnings were made about 'talking out of turn', news got round.

'Thank you.' Tonks grasped smooth grey metal and opened her eyes to grimy daylight, the groaning of sea on stone and a dull iron clanking: the noise of a continuous loop of heavy chain winding its way between twin windlasses on either side of the sea channel between the massive granite block of the prison itself and off-lying Portkey Island, ferrying a small iron boat across Azkaban's lethal tides.

Enclosed in a small recess in a rocky outcrop, a row of hooks held a single ring. Tonks dropped her Portkey over the next. Around the outcrop, a circular path ran down to the boat slip, out of sight, on the other side. She hurried down it, trying to ignore icy blasts direct from the Arctic Circle. Nothing grew here. Grey on grey surrounded her, no single trace of green except in the granite. And then the clanking stopped.

Tonks ran.

Clearing the rock wall, she saw the boat, under the stony overhang of the prison's entrance just off the slipway, heaving in a confused and leaden swell. In it three figures stood precariously, two of them struggling to control the third who, as she watched, fell and was swallowed by hungry water. Tonks morphed and spread her wings, gliding low over angry, rolling grey, before plunging in with barely a splash.

Briefly, Tonks was grateful for Charlie Weasley's not infrequent pontification upon his favourite subject. As expected, the dragon flew easily underwater, had no problem discerning the rocky underwater boundaries and found that she had a near eidetic memory of the cliff face above. Dragons,' Charlie Weasley had said, 'have an electrical sense. It helps them avoid power lines.' Dragon-Tonks found that she could 'see' something kicking hard and sinking slowly: Snape, fighting in the water, the only other living thing down here, apparently trying to chew off his heavy manacles. As she got closer, his hands came out as though to push her away and she thrust her head into the circle made by his arms and the restraining chain, twisting so that Snape's body rode on her back between her wings.

Away from the boat, she surfaced and heard and felt Snape draw a shuddering breath. Her keen eyes found Fowler and Murchison, crouched in their boat, peering over the side. With a clunking and jerking of chain, the windlasses started up again. The Aurors in the boat exchanged glances, sat down and fixed their eyes on the prison entrance.

Tonks flew, or swam, to where the fallen ceiling of a sea cave provided an easy way out of the water, dragged herself and Snape up onto it and morphed back. Encircled in Snape's arms, his face inches from her own, she was dismayed to discover that he looked murderous. He hauled them both into a sitting position and wrenched his arms over her head, the swinging chain catching her ear as he pulled himself away from her. 'Ms. Tonks, did I ask you to interfere?' Coatless, Snape's wet linen shirt clung to him. He scowled and attacked his cuff with his teeth, tugging at a button.

'Didn't you?'

'No. I did not. Stasis charm.' He indicated the button. 'Tides around Azkaban are spelled so that anything in the water washes up onto the island. In a few hours I'll fetch up on the shore below the graveyard. Bodies don't rot here, there's nothing in the soil, so when Hogwarts request that mine be returned to them, your friends will notice nothing unusual. After I've been revived, I'll leave the country.'

To avoid chained corpses turning up in muggle fishing nets, Tonks supposed. It was a plan. Of sorts. 'I hope you're going to poison Umbridge before you go,' she said. She didn't dare ask about Murchison and Fowler and whether Snape had jumped or been pushed. 'Or have you forgotten that I owe you a Life Debt?'

'You don't.' A dirty look and Snape returned to his chewing.

'Knockturn Ally?'

He lowered his wrist. 'I trained as a healer.'

'You might have trained as a Healer but that wasn't standard Medimagic. The only way that could have worked was by tying my life to your own and, if I'd died, you might not've been able to untie it; especially if the integrity of your magic was compromised by the year you spent roped to Dumbledore. You might find that you've more than a few loose ends. So, once, for mending my skull,' Tonks held up her hand and bent down a finger, 'and once for coming to Knockturn Alley in the first place.'

'Perhaps you've forgotten my own history with Bellatrix.'

'You risked your life to save mine.' Tonks bent down another finger. 'And once for warning my parents that Voldemort was after me.' Another finger. 'Life debts; and even if none of them were certain, three's the charm. People have lost their magic, even their lives, through failing to. . .'

'You saved my life when you turned into a dragon.'

'Doesn't count. I also saved my own life. And that's without considering other times like when you sent Dumbledore to the Ministry after Potter and his little friends when I'd managed to dent myself falling down steps.'

'Fine. I absolve you of any such debt.'

'And Potter? Have you absolved him too? He failed to protect you. He'll have to avenge your death.'

'Only if he knows there's been foul play.'

'He'll find out! And this is Harry James "If there's trouble, I'll find it and poke it in the eye with a stick" Potter we're talking about here. Harry's a good kid, I like him, but the little bugger acts as if he thinks he's indestructible.' Tonks shook her head. 'There are times I could quite cheerfully strangle him.'

'There isn't time for this.' Snape gestured towards the boat, now on its return journey, snarled and took another wrench at the button. Tonks drew her wand. Minerva, she thought; she visualised Snape and herself with Azkaban behind them, help! A sweeping gesture caused a large silver shape to emerge from her wand, and turn climbing towards the South, before accelerating into the sun's brightness.

It wasn't a wolf.

'What was that?' Snape asked, without any intonation whatsoever.

'My Patronus,' muttered Tonks.

'What sort of Patronus?'

'Some sort of eagle?'

'Unless I'm very much mistaken, Ms. Tonks, that was a vulture. Why do you have a vulture for a Patronus?' Tonks had become exceptionally good at saying nothing. 'You do not want someone like me in love with you, Auror Tonks,' exploded Snape.

'But that's what I've got, isn't it?' The words were out before she could rethink them. He looked appalled. 'What?' she demanded.

'What have you managed to swallow this time?' he seethed. 'Clearly, Nymphadora, you shouldn't be allowed out on your own. Your rationality seems to be questionable at the best of times.'

'I'm not irrational,' she protested. 'Not more than the magical population generally. Most of my family, on my father's side anyway, are quite sane.'

'And choosing to marry into the Black family was what?'

'She slipped him a love potion.' Tonks gave him a twitch of a smile. 'Something she'd found in the Black family library. No known antidote.' Her smile broadened. 'You probably need to watch out for my mother, Severus. She thinks it's about time I'd found myself a nice boy.'

Snape's expression switched back to murderous. He wrenched loose the button and spat it into his hand. 'I charge you, by your Life Debt to me, to stay out of this.' He put the button back in his mouth and stepped into the icy water. Tonks watched gravity and the current take him.

'You absolved me of that,' she said, morphed and slipped in after him.

Thanks to Athena Keating-Thomas for the vulture suggestion (see favorites: 'A Question of Form', her link about vultures is particularly helpful), and to Greyfalcon for feedback..