AN: I'm sorry that this took so long, I'm involved in two weddings atm so my creative impulses have a lot of other outlets, however I was staring at this yet again when I realised that the problem with the chapter was that I was trying to stretch it out until it was my normal word count when really it ends here.

Also I do not own HP

Slytherins secret

Chapter eighteen: disarmament

When the papers vanished Vernon immediately turned menacingly towards Harry and screamed "what freakishness is this boy!"…or at least tried to, what actually occurred was that he turned a violent shade of purple and in a level tone asked "what just happened Harry". Words which, judging by the stunned look on his face, came as a shock to him as well as everyone else.

Harry was unable to supres his satisfied smirk this time, but he felt even Salazar couldn't fault him, since what he really wanted to be doing was shouting for joy and bouncing all over the room.

A vein started throbbing in Vernon's temple as he exclaimed "what the….. just happened?"

Harry joined his aunt and cousin in staring in shock at Vernon since he had actually left a gap of total silence where the usual epithet would have been. He'd known that the Dursleys were required to keep 'appropriate behaviour and decorum towards their ward at all times' but this was hilarious.

An aborted laugh escaped from behind his quickly raised hand which brought Petunia in to defend her flabbergasted husband. Harry was delighted to note that her shrill shrieking had reduced in pitch and volume from just five minutes previous "What's so funny Harry?" she asked in the reasonable voice she normally only used when speaking to the neighbours, Harry could see she had tried to call him boy and failed due to the pause and her mouth moving soundlessly.

Harry pasted a polite expression on his face and replied politely "Well Aunt, I was surprised to hear Uncle Vernon ask what was happening, after all he's the businessman and the terms of the guardianship contract were very clear."

"This is the contract?" she asked "How can it affect us, we aren't magical, your world has no jurisdiction here, besides nobody cast a spell?"

"Except in the matter of a minor magical child, action against a magical citizen or location or in the disbursement of money that is true, although not all Wizards stick to it. My mother was descended from a squib line so presumably you are too…" Harry was cut of which surprised him until he realised that the contract would consider what Petunia had to say important to his welfare (the contract was likely the only reason she hadn't supresed the instinct to tell him)

"I'm not related to some magical…people, Lilly was my half-sister, my father" She visibly struggled to stop herself speaking "my father….my mother married Lilly's father whilst she was pregnant with me."

"Merlin's beard..." Harry murmured

"Language young man!" Petunia snapped, looking confused that she had been able to.

Harry decided to be reasonable "sorry Aunt Petunia, but this could be a problem, Dumbledore claims that your relation to my mum keeps us safe but if you are only half-sisters and you don't have any Wizarding blood we can't be very well protected from the little I know."

"Hummm we'll discuss this later, now explain the contract affecting me since we've amply identified that I'm not one of you…please" the last was forced past unwilling lips making Harry smile slightly.

"Yes, Ok, well you are right, if this was a random contract about a job or something it wouldn't work, but every living thing has a little magic. The killing curse momentarily negates all magic in a target and is equally fatal in wizards and…normal people, so you have a little magic keeping you alive. The contract mostly uses my magic as witness to seal a little of yours to identify you and attach to and will continue to run because of Gringotts' magic which Wizards aren't allowed the secret of. It affecting you would be illegal, (Harry could see Vernon attempting to erupt into vitriolic commentary) except that I'm a minor magical child and this relates to my care, and there is money involved which makes it Gringotts' legal business. I'd imagine that the lines about appropriate behaviour and decorum are what affected your speech though I was mildly surprised to see it affect curse words."

"So what does this contract do to us, I read it but obviously not clearly enough?"

"It simply makes you act in a manner that is appropriate and fair to all children in your care, although you are welcome to feel differently about those children, and gives details about minimum standards of care in relation to the family situation and levels of income etc. If you were magical it would cover what spells are suitable and what we should be being taught, although you are not it will still cover appropriate education but I expect Hogwarts and Smeltings have that under control.

That's…all?" Vernon asked.

"It gives detail and guidance on many situations so that the magic doesn't over-react or under-react to situations and if a response seems inappropriate then it can be appealed and added to the contract. Punitive measures are unlikely, the contract largely prevents breaches from occurring but in some situations such as extended passivity in face of a known problem it might enact the punitive clauses.

"Oh" Petunia sat still thinking for a moment, "boys could you give us a minute to think about this? Harry there is food in the fridge, just grab something to make a balanced breakfast and please both of you go to your rooms, Vernon and I need to talk."

Half an hour later a happy Harry had dashed of a quick letter to Madam Pomfrey letting her know the good news and demolished a breakfast that roughly corresponded to his diet plan. He was feeling rather good about himself and decided to give his relatives a little space by going for a quick walk. He knocked on the kitchen door and said "Aunt Petunia, I need some exercise can I go for a walk?" upon receiving a distracted nod he set of to start his planned exercise routine never noticing Dudley listening from the top of the stairs. Unfortunately when he had finished his run and was cooling off by walking back to Privet Drive Dudley was waiting for him and he'd managed to find Piers in the half hour Harry had been gone, brilliant. Harry winced and tried to think of a way out given that he'd worn himself out to much to run far, whilst cursing himself for forgetting that the contract didn't affect Dudley.

He still hadn't thought of something when Dudley smacked his fist into his palm and sneered "Just because mum and dad are worried about putting you in your place doesn't mean I can't show my friend and my cousin what I learnt at school, so let's teach you how to box freak!" Harry rather thought today was going downhill.

When Harry and Dudley got back to privet drive Petunia took one look at them and shrieked. Honestly Harry didn't blame her, he knew he'd had the worst of it but even Dudley looked worse for the wear, on top of that they had been delivered by an irate Mr Polkis as having been fighting by his house.

Harry had gained some amusement from their resulting punishment but since nothing could be said other than that it had been two on one and Petunia truly believed that her ikkle Duddiekins was a sweet angel they had ended up with even punishments. Of course having to punish Dudley prevented them from doing more than confining them to their rooms to do homework and not getting any pudding. Dudley was horrified after that evening to find that this punishment was truly being applied to him since it was the worst punishment by far that he had suffered in his spoilt life. Harry supposed that it was almost worth it just for that, the fact that he had been given the most basic healing slaves before he left helped since his swelling eye was a spectacular bruise but it didn't actually hurt, likewise various other bruises and scrapes, he'd not managed to give Dudley a shiner but the git had still got a few good bruises even through the blubber and Piers a few more, that was probably why Mr Polkis was so angry.

All in all Harry thought whilst eating the snack Dobby had brought him and working on his first draft of the History essay (he'd finished all of his reading for 1st, 2nd and the extra info in that subject) this wasn't too bad. He'd rather be elsewhere of course, but unlike in previous years not anywhere but here. With that surprising thought in mind he finished his draft essay, and pulled some parchment to write to Neville, the various Weasleys and Madam Pomfrey smiling contentedly.