Herpo was an Ancient Greek Dark wizard, infamous for being a pioneer in the field of the Dark Arts. He was the first known wizard to create the Basilisk and the first known to create a Horcrux. He was one of the earliest known Dark wizards and his work left a lasting impression in dark magic during the 20th century.
Harry knew what kind of knowledge that this book would hold based on how its labeled. He knew it would be the most powerful and darkest kind of magic that he would ever be able to learn. And that excited him. If his hunch was right he might have all the research in magical knowledge of Herpo the Foul.
Harry opened the book and started to read. The book was written in the manner of field notes. Quick and to the point which would allow him to gain as much information as possible very quickly. It also meant that Harry could gain the knowledge within the book quicker. In truth, it seemed to be all of Herpo's knowledge rolled up into one single book. Guiding someone on how to become as strong and even stronger than the great dark wizard was. Harry quickly learned many things about different kinds of snake types of magical beasts such as the Basilisk, Horned Serpent, Ashwinder and Runespoor. Even some dark magical creatures such as Chimaera, Manticore, Lethifold and even some about Dementors.
As Harry read the book he could feel the knowledge contained within printing itself into his mind and soul. He felt his magic and soul growing stronger and then he felt it. He felt another soul fragment of Tom in the house. He stoped reading and held out his hand to call the object with the soul to him.
Harry looked at what he now held in his hand. It was a locket that the crest of Slytherin. As he held it a dark mist came from the locket and was absorbed by Harry. As that happened he felt his soul get even stronger. He remembered that Tom had left multiple soul fragments scattered across britain and he couldn now collect one and soon another.
Harry put on Slytherin's Locket and felt his magic reach out and connect to the locket. He felt knowledge flow into his mind. Harry now knew that Salazar Slytherin had left the locket to pass on all of his knowledge and secrets to the next Lord Slytherin and that all the knowledge that Harry and all future Lord Slytherin would be saved in the locket and pass to the next Lord Slytherin as long as they had the locket.
Harry stoped for a moment then made up his mind. He left the book on his desk and apparated to Gringotts. He walked through the doors and made his way to the head teller's counter to speak with the head teller, Ricbert. As Harry stoped at the counter he spoke in a low voice "I need to meet with you in private to go over something in the valt of one Bellatrix Lestrange (née Black)." After Harry said that Ricbert looked at him for a moment then noded and said "Very well follow me ,Young Lord." As Harry followed Ricbert to the room he saw a beautiful girl with mesmerizing silver eyes. The girl looked to be his age. Just before he entered the room their eyes met and he knew that the girl was one of those he was to wed in the future.
Harry felt this in his very soul. His soul which had grown stronger after all the changes that head happened to him. As he walked in the room with Ricbert, Harry sat on couch across from the goblin. As Ricbert sat down he asked "What is it that you hav come for exactly, Young Lord." Harry spoke calmly and said "I am here because it has come to my attention that Bellatrix is hiding a horcrux in her valt." As he said this Harry saw a look of discussed appear on Ricbert's face. "Young Lord, this is a most revolting act!" As Ricbert took a breath he spoke again "By any chance would you have an idea of what it looks like?"
Harry looking at Ricbert said "It should be an artifact known as Hufflepuff's Cup." Ricbert looked at Harry's face said "Do you have any way of destroying the horcrux without damaging Hufflepuff's Cup?" Harry noded "Yes I do have a way and once the cup is clean I will be taking it with me as it is an artifact of one of the house is I am Lord of."
It was not long before a goblin returned with the cup in hand. As soon as Harry saw Hufflepuff's Cup he could feel the fragment within it. He held out his hand and the cup was promptly handed over. Once Harry held the cup he felt the fragment try to fight against him.
It did not take Harry long to subdue and absorb the fragment, and as soon as he did he felt the strength of his soul and magic grow immensely. As soon as he finished with the fragment Harry looked at the goblins and spoke. " While I'm here, I believe I will fulfill some of the things I was meaning to do as the head of house Black." When he said this, the goblins nodded and Ricbert asked. " What is it that we can help you with while you're here. Great Lord."
Harry noded " While I'm here, I would like to dissolve the marriages of Bellatrix Lestrange and Narcissa Malfoy (née Black). As well as look into the arrest and possible unlawful imprisonment of one Sirius Orion Black." Harry then added. " I would also like To see if it is possible to have Bellatrix released into the custody of house black So that her punishment may be overseen by her family. Also I will be henceforth welcoming Andromeda Tonks (née Black) back into the family. Along with any children she has had." Ricbert noded " This can all be done, Great Lord, but in the cases of Bellatrix and Sirius there might be some time before anything it can be said for certain." Harry noded " That is fine. So long as everything I have said is done to the best of your ability. And while we're at it, I would like you to find me a trustworthy solicitor." Ricbert thought for a minute. " I believe one Ted Tonks husband of Andromeda Tonks would be a good fit for what you would need, Lord." Harry noded " If it's possible I would like to meet them while I'm here as well as any children they might have." Ricbert noded again "That can be Is arranged, Great Lord."