Harry Potter and the Mage of Swords
Harry Potter was quite perplexed. He had just recently found out that he had an uncle from his Aunt Petunia. Apparently, his name was Chrysanthos Evans. He had been an executive for some tech company and had decided to live in Japan as he thought that the future of technology was located there. To the joy of his aunt and mother, he managed to gain the attention and attraction of a local woman who was from a respectable family in the city where he was living. Unfortunately, the Evans luck never seemed to stay in their favor for very long. A few years after they had gotten married, a large fire swept across the city of Fuyuki, killing over five hundred people and displacing thousands more. Due to all district records from before being destroyed, Uncle Chrys, his wife, Satsuki- nḗe Muramasa- and their seven-year-old son Shirouta were believed to have perished along with the other victims. He had planned on learning more about his mother's side of the family from his aunt, but, unfortunately, Vernon's Aunt Marge visited, which led to another bout of accidental magic whereupon he blew her up with an Engorgement Charm. That led to him hitching a ride on the Knight Bus to the Leaky Cauldron, where he was met by the Minister of Magic himself, Cornelius Fudge. The minister seemed oddly relieved that Harry had safely arrived. Apparently, there was a general panic over the fact that Sirius Black, an imprisoned supporter of Voldemort had escaped from Azkaban—the Wizarding prison located on an island in the Black Sea.
After a suspiciously vague explanation as to why Black would be hunting for him, the Minister had left him with a warning to stay in Diagon Alley for the remainder of the summer break, and to not go wandering off into the other side streets. He was then led up to his room, where he found Hedwig waiting for him. While heading up the stairs, an idea had popped into his head. He decided that, in the morning, he would ask around the area for any information on whether or not the Wizarding World had something akin to DNA tests that would be able to locate or reveal past and current relatives. After a night of mostly restful sleep, he walked downstairs to the inn's lobby, where he inquired of Tom and the other patrons as to whom might perform such a procedure. All of the information he received pointed towards the goblins—which made sense, since they had to have safety features in place in order to get around Polyjuice potion and to prevent vault theft. The next step, then, was a trip to Gringotts.
The interior of the bank had not changed much over the past year. There were still the same sets of raised desks upon which the goblins sat, with lines full of wizards and witches waiting to speak with them. He walked up to one of the desks and requested the best goblin to speak to about blood and inheritance tests. They complied and directed him to an office where he was met with a grizzled old goblin by the name of Ironfang, who happened to be the account manager for the Potter family. Ironfang explained that all that was needed for the performance of the procedure was to prick his finger with an enchanted goblin-made dagger, and let the droplets fall onto a connected sheet of parchment. Only three drops were required for the enchantment to take effect, at which time, the parchment would show in detail the person's lineage and holdings, as well as a list of relatives and house alliances. The following names appeared on the sheet: Andromeda Tonks, Sirius Black (Godfather), Narcissa Malfoy and Shirou Emiya—formerly Shirouta Aletris Evans—son of Kiritsugu Emiya. He turned to Ironfang and asked how it was possible for Shirouta to be alive. The goblin said that the man who had adopted him was a former assassin for the Mage's Association—a separate entity from the Ministry—who had come to them for help with forging records for the boy, with the purpose of adopting him. As a favor to the man for previous services rendered, they had assisted him in such an endeavor. Apparently, the boy and his father were the only survivors of the Great Fuyuki Fire. From what they knew of the now young man, he was still living in Japan, in a property his adoptive father had purchased with the local yakuza group's help. With that resolved, Harry turned his attention to the second name on the list: Sirius Black. It didn't make any sense that his parents would name a Death Eater as his godfather, especially when they would have fighting in the war against Voldemort. Ironfang then said that as part of the magical oath that is taken up as one of the terms of godfather in magical society, he would have been unable to harm him.
As he left the bank, Harry pondered his situation. Why had Shirouta not contacted him after all these years? By all accounts, he would have been sixteen by now. Perhaps he didn't know of Harry's existence? He knew of the magical world, though. Surely, he would have heard of the name Harry Potter. It was a household name by this point throughout the entire magical world. He had gone to Gringotts for answers, but he was left with even more questions than before. He knew what he had to do next—send an owl to his cousin.