I know it's a bit early but Merry Christmas!
As the days went, things for Harry Potter were getting better and better. The Dursleys gave up on him and he couldn't be happier. Shortly before September, Professor McGonagall came to talk him about his education.
"Hello, Professor McGonagall!" exclaimed the young boy.
"Hello, Mister Potter. I came to talk to you about your education."
"Will I go back to school?"
"No. We won't send you back to Muggle school. I will have Remus Lupin come teach you. He's a wizard and was a friend of your parents."
"Really?"
"Yes. Dumbledore will pay him."
"When will my lessons start?"
"On September 1st."
"What will I learn?"
"Things like English, maths, Latin, potions, herbology, wizarding history, wizarding culture, understanding how our world works, etc."
"That will be great."
"It will be the best way to prepare yourself for Hogwarts."
On September 1st, Harry was eager to start his lessons.
"Hello Harry!"
"Hello Professor Lupin!"
"You can also call me Uncle Remus, since I really knew your father.'
"You did? Right, Professor McGonagall told me about it."
"We met on our first day of school. We were part of a group called the Marauders and we used to always pull pranks. I will even show you a picture of us with your mother."
Monday mornings were spend on Latin and the afternoons were spent on German. Harry was surprised that his teacher spoke the language, but Remus told him that he was working for a German wizarding research magazine where he published articles about Dark creatures. Tuesdays were spent on English and magical creatures, including Pokémon. Wednesdays were spent on herbology in the morning and potions in the afternoon. Thursdays were spent on mathematics and science and Fridays were spent on wizarding history and understanding how the wizarding world works. The lessons weren't too demanding since Harry still had five years before starting his Hogwarts education, but he still needed some grounding in wizarding education. While Harry had to study with Professor Lupin from 8:30 AM to 4 PM, half of the time was spent talking about the Marauders.
The days came and went and it was Halloween. Harry was invited to the Burrow in the evening to spend time with the Weasleys. They also received the news of the death of Neville's parents. Their torture sharply shortened their lifespan. When Bellatrix Lestrange heard about it, she started laughing maniacally from her cell in Azkaban.
Everyone was sitting in the kitchen eating their dinner, when suddenly, Mr. Tibbles started acting up weirdly.
"What's wrong?" asks his human.
Professor McGonagall turned into her Animagus form (a Torracat) and starts talking to the Meowstic. She then turns to Percy.
"We may have been deceived for five years."
Scabbers knew what the Scottish witch was talking about and started running away.
"Petrifucus Totalus!" shouted the Transfiguration teacher while pointed her wand at the Hawaiian Raticate.
"What's the meaning of this?" asked Percy, scandalized by what was happening to his pet.
Minerva didn't answer him and kept using magic on the rat. Suddenly, what was once a Raticate turned out to be a man who everyone thought died five years ago, leading everyone to scream.
A.N.
Why McGonagall is a Torracat and not an Incineroar? It's because she feels that the latter is too humanoid. Also, note that a Pokémon Animagus is not as powerful as a real Pokémon.
Scabbers