"Congratulations to Boy-Who-Lived, you've successfully killed yourself!"
It took him a while to recognize where he was. How surprising, he was lying on the familiar bed he had always laid on during his six years in Hogwarts, in - the - dormitory - of - Gryffindor - decades - ago. For some magical reason, Harry at age 31 - The Chosen One, a powerful Auror and the greatest wizard of the century - had gone back in time and became a young troublemaker studying at Hogwarts again.
He thought this was related to the spell he was doing right before opening his eyes and shrunk back to a kid. To know the cause of this dilemma though, he would have to go back in time a little more to tell the tale.
Normal wizards balance their magic cores when they reach adulthood, which is 17, and from then their magic cores will steadily grow depending on their work and living environment.
But Harry was never a normal wizard, even after reaching adulthood his magic core was still expanding at a concerning pace. His core was growing so fast he could swear to Merlin’s beard if Voldemort returned two years later than his initial return he could confidently give the damn man Avada a few times before he could blink.
Of course everything has its downside. His enormous magic pressured his core a bit too much than he’d like. If he didn’t find a way to release it. The Chosen One could pretty much become the first wizard in history losing his life because of a magic core explosion.
Through the know-it-all Hermione’s help (of course he wouldn’t tell her what was happening or else the wizarding world who saw him as the symbol of hope would become a mess that he’s not sure he could handle), Harry found the reason for his rapid growth of magic.
Thanks to his beloved family tree, thanks to the Potter bloodline and thanks to the Potters’ damned ancestors who were hit with some damned curse, every Potter will have to find their soulmate to balance their core instead of the normal way like normal wizards. And when he dug through his short memories about love, he painfully realized how much hints he obviously skipped for years till now.
In his fourth year he almost got a magic outburst when Cho Chang went out with Cedric Diggory. At that time he thought Cho was his soulmate and the idea of his soulmate going out with someone who isn’t him made his “Potter instincts” think he was losing his soulmate.
After dating Cho for a while during his fifth year, “Potter instincts” became calm again.
Then after breaking up with Cho and going out with Ginny, the damned “Potter instincts” told him Ginny was his soulmate.
Everything should have been fine if he was still together with Ginny and married her, but Harry couldn’t make her life tragic. He found out he didn’t love Ginny enough. When he had just become an Auror, while hunting for the escaped Death Eaters, Harry was frequently cornered when he fell into their traps, having to choose between saving Ginny or capturing them. He didn’t hesitate and chose the latter, making the girl suffer a torture spell, which was not good in any way. His job was a Auror, not just him but his family would soon be involved in his dark wizard hunts. Them being together would just increase the chances of her being in danger, and Harry always put his missions before her, so he decided to break up with her, freeing them both.
After that, he wasn’t interested in falling in love anymore, and “Potter instincts” decided that he didn’t have a soulmate, that was why his magic was quickly expanding again.
He tried a few ways to release the most magic he could, but it wasn’t a long-term solution. When he reached age 31, his core was at its max.
This was the main reason that pushed Harry to search in ancient documents (with some outside help of course), trying to find the best solution to this dilemma. And Harry actually found a way, in a very off-guard page belonging to a very thick book, mentioning a destined soulmate that everyone has.
A destined soulmate is different from a soulmate from any perspective. Wizards don’t necessarily have to pair with their destined soulmate, the world is too crowded yet you only get one destined soulmate anyways, but once they have paired, it will be a very strong bond that no spell or curse can break. During recorded history there’s very few destined couples that found each other, the only thing in common about them is they’re all great figures of the wizarding world, like Merlin and King Arthur.
Harry decided he must find his destined soulmate in any way. Part of the reason is he needs someone to help balance his magic core. The other part is two soulmates would always be similar, he’s a strong person so his soulmate must be too, he would have his own family without worrying whether they’d be able to handle the dark wizards’ harassment.
Once again, with outsiders’ help, Harry found a navigating spell deep in Hogwarts library's forbidden zone. He wanted to use it to find where his faceless soulmate was.
Whatever comes must come, or like Murphy’s laws: anything that could go wrong will go wrong. His unstable magic core had a teeny tiny bit of problem while he was casting the spell. After that, like he had said, Boy-Who-Lived Harry Potter woke up in - the - dormitory - of - Gryffindor - decades - ago.
This, described in a rhetorical way, would be, The Chosen One, despite everything, is determined to find the love of his life, even if time, space and even life and death comes between them. Frankly speaking though, Harry thought, perhaps Rita Skeeter would name her article "The Chosen One successfully became the first wizard in history to kill himself because he can't find his soulmate" if she ever found out about this. Maybe even his enemies would send him the rarest postcard in the world with the most castigated letters on top: "Congratulations to Boy-Who-Lived, you've successfully killed yourself!"
Harry tiredly got up. First he needed to know the exact time he was sent back. Though The Chosen One always missed his beautiful times in Hogwarts, it had already been decades, he can’t navigate the year just through his sleeping pillow. He needed to find Ron and Hermione and try to talk as smoothly as possible to avoid the smart Gryffindor’s suspicion spiking up.
“Hey Ron…”
Seeing his best friend about to leave bed, Harry decided to speak up. Ron replied with an angry huff and left immediately, not even sparing him a glare.
Harry Potter :”???”
Fine, guess he didn’t need to investigate anymore, he might have already known what time it was. Harry and Ron had a lot of time when they were pointlessly angry at each other, though their sulking sessions would immediately end once one of them decided to break the tension by speaking up. If only counting his years at Hogwarts, the only time Ron was still angry even after he spoke first was his fourth year, when the goblet chose him as the extra champion. The first round must have not started yet since after he was hurt by the Hungarian Horntail they’ve already made up.
“Okay, calm down Harry Potter, now not only you have to face a scary dragon in a fourth year’s way you also have to expose Barty Crouch Jr in a way that no one would suspect a thing…”
If he was still 31, he just needed a huge Stupefy charm to overpower the dragon with larger magic. But of course, everyone then knew Harry Potter as a kid who hasn’t even learned any lessons in the year…