What if harry had no magic?

If Harry was a squib:

Book I PS

 Nothing changes from the book until Harry puts on the sorting hat and is sorted into "Muggle House". This is when the world finds out Harry is a squib. Muggle House is famous for its wild parties. Muggle House unlike the other houses is spacious with its own pool, gardens, banquet hall, and concert hall but lacks a Quidditch team. The Muggle House students study things like Basic Magic Theory for Squibs, a kind of special ed. class. Also, muggle topics like Eknomics, something called Maths, and once a year Mr. Weasly will do a seminar on topics like Why Muggles Are Obsessed with Rubber Ducks or Eklectric Plug Theory which is quite popular. 

 Professor Quirrell manages to get to the mirror but cannot get the stone. Dumbledore arrives back from his meeting and confronts Quirrell. Quirrell experiences the power of the elder wand and The Dark Lord fails. Harry, Ron, and Hermione become good friends.

Book II CoS

 Dobby does magic at the Dursley's and Harry gets an automatic first warning Howler from MoM. Harry and Ron fly the car to school which results in a wild school opening bash at Muggle House. The CoS is opened and members of Muggle House are being attacked. Speculation swirls about whose responsible because Draco hates Muggle House and rumors suggest that Harry is consorting with snakes. Muggle House may be for squibs but they are not stupid and arm themselves with side arms and when ever they see a Slythern student they release the safety. Harry finds out where the CoS is located and confronts Tom Riddle. Harry kills the basilisk with his Colt 45 and stabs the diary with the fang saving Ginny. The Dark Lord fails. Party at Muggle House!

Book III PoA

 Harry punches the lights out of old drunk Aunt Marge and runs away. The muggle EMTs patch Marge up and Harry winds up throwing parties at The Leaky Cauldron. Sirius Black realizes that Peter Petagrew is at Hogwarts and escapes from Azkaban to protect his God son Harry. Peter finds out and scampers off to Albania. Sirus meets with Lupin, Harry and the gang and explains that he is innocent. They convince Dumbledore and Sirius gives up the chase and moves back home.

Book IV GoF

 The Triwizard Cup goes off as planned. Rita Skeeter begins writing stories about the scandalous international parties at Muggle House. The Dark Lord needs the flesh of an enemy for his comeback potion and even though Harry is an enemy he is also just a squb in Muggle House and not worthy of consideration. Since Bertha Jorkins is at hand she will have to do. The Dark Lord Rises again and gathers his Death Eaters. Snape feels the dark mark burn and informs Dumbledore. Dumbledore and MoM disagree that the Dark Lord is back and Dumbledore revives the OoP.

Book V OoP

 Dolores Umbridge a devoted reader of Rita's work is disgusted by what she learns about Harry and the Muggle House parties and sends Dementors after Harry. Harry narrowly escapes and runs to the safety of the Dursley's house. Professor Umbridge is sent to Hogwarts to stop the Muggle House parties. The Dark Lord and Harry discover that they have a connection to each others mind. Harry doesn't understand and Dumbledore won't tell him what's happening. Ron and Hermione lead a revolt against Umbridge oppressive regime. The Dark Lord convinces harry that Sirius is in trouble at MoM. Harry is friends with the DA study group and ask them to help. Harry and the DA go to the MoM to confront the Death Eaters. Harry is well armed and can be deadly as long as the DA can shield him from magical attack. Soon the Dark Lord arrives and Harry has to hide until Dumbledore arrives and secures the perimeter. MoM arrives and realizes that Voldemort is Back. Sirius is killed and Harry skips the end of term party at Muggle House.

Book VI HBP

 Dumbledore uses Harry to recruit professor Slughorn and drops him off at the Weasly's. Harry begins Special Studies with Dumbledore and learns all about Tom Riddle. Harry is not in potions class so Ron finds the potion book and wins the lucky potion. Ron uses the lucky potion to improve his Quidditch game, win Lavender's affection, and finally win Hermione heart. Harry uses some of Ron's lucky potion to get the memory from Slughorn. Poor Draco has been ordered to kill Dumbledore and begins working on a plan. Dumbledore takes Harry to the cave and retrieves the locket and upon returning is killed by Snape. Snape flees. No parties at Muggle House this year.

Book VII DH

 Back in the old days Snape had a thing for Lily and developed a rivalry with that Muggle loving James Potter. Snapes prejudice leads to Lily preferring the company of James and attending Muggle House parties. Snape grew to hate Muggle House because he was never invited to parties. Snape becomes the new Headmaster and bans Muggle House parties. 
 Harry, Ron, and Hermione begin the quest for the Horcruxes. We pick up the action when Harry looks into the pensive and sees Snape's memories. Harry goes to meet the Dark Lord and sacrifice himself. Harry Meets Dumbledore in limbo and Dumbledore tells him all the things he should have told him in his first year. Harry throw a punch at Dumbledore but his fist passes through because Dumbledore is a ghost. Because Harry was a horcrux he has powerful protection which has now broken but he can return to life if he wishes. Harry returns witch leads to the final confrontation in the great hall. Because of Harry's sacrifice he has given protection to his fellow students Now the Horcruxes gone the Dark Lord is vulnerable. Harry guns down Voldemort in the great hall and the Death Eaters surrender.

Years Later

 The Potters meet the Weasly's at Kings Cross and casually wave at Dolores Malfoy. When Draco was younger he found he liked taking Pansy Parkinson's Poly-juice Potion and finally made the gender change permanent. He changed his name to Dolores after his favorite teacher. Harry's kids turned out to be wizards and they all lived happily ever after, the end.
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