One shot about Harry and his patronus charm. It's not canon. But that's kind of the point to fanfiction haha. Please enjoy and review if you would like to.
A patronus charm, as Harry found, was one of his most complex magics that he used on a nearly daily basis. His own knowledge of the spell had developed over his years on the Auror force, resulting in a stronger and longer lasting charm than he had back in his school days.
The patronus charm was known to change when a witch or wizard went through extreme emotion or when they fell in love or obsession with another person.
But as Harry discovered, with high amounts of power, one could have many forms of their patronus, depending on the memory they used while conjuring the mystical animal.
And through his training, Harry had mastered 4 different forms of his patronus.
The first was his original form, the stag. When he thought of his parents, or the Weasley family, or Sirius Black; this was the form his patronus took. The stag was his strength and the strength of the people who loved him. Traditionally stags were also symbols of regeneration or rebirth. With the amount of death in his life, Harry took this represent an everlasting love that was reborn in his love of his friends, wife, and children.
It wasn't surprising that the second form of his patronus was something he discovered while on a mission with his best friend and closest confidant, Ron Weasley. They were on the hunt for yet another up and coming Voldemort want-a-be in an old dark abandoned castle. The cold air wasn't unusual for the climate and desolation of the building, and so did not warn the two men of the danger. It was like the summer before 5th year, in a flash he and Ron were tossed across the room. Ron nearly flew off the staircase completely and was holding on by one arm. The dementor had no limitation of needing ground beneath its feet and so was hovering next to Ron, attempting to perform its most devastating move, the dementor's kiss.
Harry raised his wand and all of his memories of Ron came rushing to him. The beginning on the train. When he stood on a broken leg to protect him and Hermione from Sirius Black. When they trained together to prepare for the 3rd task in the Triwizard tournament. When he saved him from drowning while retrieving the sword of Gryffindor.
He felt as though he must be glowing from the sheer amount of warmth and affection that he had in that moment for his greatest friend.
And with such a focus on Ron, when he cast the patronus charm, he was only slightly surprised to see a much shorter creature, a terrier, rush out from his wand and sprint fearlessly at the dementor. When it was suitably banished, Harry helped Ron back over the railing of the staircase. The small dog remained, and starred up at the two men, wagging its tail. Even after saving their lives, it still wanted to do more, to help its friends more.
It wasn't the first time Harry and Ron shared a proper manly hug, and it wouldn't be the last.
His second alternative form came to him in far less death-defying way. Which is how his other best friend, Hermione Granger preferred discovering things.
When he and Ron told her about his patronus changing forms, Hermione immediately did what she did best and went to the library. After hours of reading through books that were all suggesting that he should be reassessing the level of intimacy in his relationship with his oldest friend, she found an old book from one of the first aurors in Russia. Unfortunately, none of the three of them knew Russian.
And so began the long and slow process of translating the text using Russian dictionaries. Ron was forced to leave them, his commitment to helping George in shop the following morning pushing him to get more than a couple hours of sleep. Harry and Hermione had no such limitations. And 5 and ½ hours later, the thankfully short (it was more of journal than a book) text was translated.
Alyona was an Auror of high regard in her time. The cold climate of Russia meant that dementors were particularly unpredictable creatures, and so Aurors were highly trained in defeating the beasts. Alyona discovered through her own research that she could have her patronus take on the form of another's patronus if she felt a deep and emotional connection to them. Unlike her native patronus this one was particularly powerful as it forced the love and affection of the person she was thinking about to the surface and created another non-corporeal patronus around the castor. Alyona was able to conjure three patronuses, her original wolf, the field mouse of her younger sister, and the grizzly bear of her girlfriend. Being able to cast many forms also allowed her to cast many patronuses at the same time.
There was nothing written about there needing to be in a life-or-death scenario. He pulled out his wand, Hermione eyed him suspiously but said nothing. He let the memories of his reliable and intelligent friend flood his mind. Without the panic of fighting a dementor, he was allowed time to truly bask in the warmth these memories filled him with.
Hermione wasn't always the strongest fighter. He remembered when they had jumped through the trapdoor in the first year, in her panic she had forgotten that she could conjure fire rather than use sticks. But he also remembered when they fled the Lovegood's house, when the house had blown up, she had the presence of mind to not only hide Ron, but to also perform an Obliviate charm, destroy the ground from under the three of them, and disapparate before hitting the ground, allowing the death eaters to see her and Harry, thus saving Mr. Lovegood's life.
He thought of her patronus, the otter. Initially one might not see the connection between the studious Hermione and the playful otter, but as one of her closest friends, Harry knew better. Otters were incredibly intelligent animals, but more importantly the patronus provided insight onto what Hermione strived to be. Unlike himself and Ron, Hermione struggled to be adaptable and reactive. She preferred to plan and think before she acted. This was contrary to the go-with-the-flow otter, which moved with the current and changed its path to avoid any obstacle in its way.
Focusing on these thoughts, his love for his best friend surged around him like before and with a wave of his wand, a bouncing otter emerged and swam through the air around him and Hermione. In the typical Hermione fashion, she grabbed him for a fierce hug, tears in her eyes. When she finally did release him, it was to begin her own practice of the charm; there was no one more competitive than Hermione.
His final (for now) patronus form was the most difficult to achieve. It took nearly 9 months of practice to finally get his stag to transform in that of the black mare, Ginny Weasley's patronus.
It was frustrating for him. This form should've been the easiest of his loved ones, as she was his closest confidant. It also didn't help that while practicing he would initially think that he had succeed, but only realise that the large hooved animal was still a stag.
Ginny's patronus, the black mare, represented her to the tee. It was motivated, determined, and desired freedom above all other things. And Harry did know Ginny. He knew what she wanted from her career, what she wanted for her family, what she wanted from him. Their deep connection was, as it turns out, was what was creating such a block for him. In his mind he could not separate Ginny from Ginny and his self's relationship.
So to prevent this Ginny suggested that he focus on a memory from before they started dating. She smacked him playfully when he suggested the time he was read her infamous poem, he would never let that one die.
No, in the end he chose a memory from his 5th year, when he wanted nothing more than to talk to Sirius about his dad. She had shared her chocolate easter eggs with him, and told him that anything was possible if you had enough nerve.
His core warmed just like it had back all those years ago, and a beautiful black mare galloped from his wand. His wife laughed and said about time, while conjuring his stag to run alongside the mare.
But in the end, as he watched the two prance about the yard, he knew that he didn't need to conjure a patronus for his loved ones to be there. The warm feelings he had for them would always exist, magic or no magic.