'Welcome to the Marauders Mansion.' A voice said

Harry looked up at the grand staircase on the left-hand side of the hall.

'Malfoy.' Harry said coldly

'Lord Potter.' Malfoy gave a small, respectful bow, no hint of mocking in his demeanour.

'Is there a reason you're here, Draco?' Sirius asked, giving nothing away in his tone.

'Yes, Lord Black, I have finished checking over the paperwork. I've filtered them all according to your political agenda and put them into labelled piles for you to sign.' Malfoy said

'Go help the house elves then.' Sirius ordered

'Of course, Lord Black.' Malfoy bowed again and left.

'Sorry about that,' Sirius said once Malfoy had left. 'I am rather stressed out at the moment. Follow me, please.'

Harry was excessively perplexed now, the whole world seemed to have turned on its head. Nevertheless, Harry followed Sirius without question. They went up a flight of stairs, through countless corridors, up another flight of stairs and through another maze of corridors. Harry was beginning to get bored with the repetition when they stopped at a suit of armour and it opened a secret passageway. The passageway was long, narrow and cold. When they finally got to a large hall. It was made of entirely grey stone and there was a slight chill in the air that prickled their skin. The hall was mainly empty except from a small table in the middle of the hall with a silver bowl on it and an equally as small sword.

'So,' Sirius said. 'I've legally adopted you but I want to magically adopt you in blood. Basically, we make the vows and the magic will confirm the blood adoption. Just cut your palm with the sword, confirm all the vows and the family magic will judge if you're worthy. Any questions?'

'Why do we cut our palms with a sword?'

'It's goblin made – made about ten centuries ago. It's a Black heirloom. Tradition to use for rituals which involve blood – which is most.' Sirius shrugged, taking the sword and cutting his palm in one swift movement before allowing a few drops of blood to spill into the bowl and handing Harry the sword.

Harry gasped in agony as he pressed the blade of the sword against his palm and allowed blood to spill into the bowl. Sirius took the sword and placed it back to rest against the table. Sirius held his hand out above the bowl and Harry and Sirius held each other's hands above the bowl.

Sirius took a deep breath.

'I, Sirius Orion Black, Head of the Nobel and Ancient House of Black, declare Harry James Potter, Head of the Nobel House of Potter, my heir and son in blood, magic and law. Will you, Harry James Potter, Head of the Nobel House of Potter, embrace your position and do your best to be a worthy son to represent the Nobel and Ancient House of Black and serve and protect your house and family, in blood, magic and law?'

'I will.'

A thin string of hot, white fire wrapped itself around Harry and Sirius' hand. It felt as though it was burning through his skin and crumbling his bone. Sirius must have felt it too, because he tightened his grip.

'Do you swear to help your family in even the most dangerous of circumstances even at the risk of your own death?'

'I do.'

Another thin white flame wrapped itself rough their hands, causing excruciating pain, piercing into and scorching his very flesh and blood began leaking from their hands and into the bowl.

'So have it been sworn, so mote it be.'

Webs of light blues flames engulfed him, scorching through his skin. So much so that he forgot who he was, where he was, lost every sense of self and couldn't focus on anything other than the pain, not a single other thought.

Harry screamed. Screamed louder than he ever had in his life.

Then it disappeared and a feeling of overwhelming joy replaced it. A type of black bird bowed to him then disappeared.

Harry looked in a mirror that had seemingly appeared out of nowhere behind him.

There was a ring of his finger, with that Black family crest of it.

'That's an heir ring.' Sirius explained

His hair had gotten a darker black – if that was possible – and slightly longer and tidier. Harry took off his glasses and found he didn't need them anymore. His eyes were sharper, as were most of his features. His nose was smaller and he seemed to have gotten taller and gained a little weight. His eyes had gone a duller shade of green (which Harry found he liked) in fact, they were barely green at all, rather a muted shade of cyan. His hair went down past his ears and his nose was smaller.

'Harry James Potter-Black.' Sirius smiled