Harry Potter, Lone Traveler, arrived in the shadow of a building. He looked around and noticed that he knew exactly where he was: Diagon Alley.
It was very early in the day, and all of those present were shopkeepers preparing for the day's beginning. As Harry walked up the street, he stopped at Flourish and Blotts and the sign that was in the window: "TODAY ONLY! GILDEROY LOCKHART will be signing books and meeting fans in celebration of his new book: Magical Me!"
Harry considered that for a long moment and then, slowly, his face morphed from a serious look to a grin. First step: Get an empty book.
Ginny Weasley, soon-to-be Hogwarts First Year, started pulling the books that she had gotten that day. As she pulled out her Transfiguration notebook, she noticed immediately that there was something odd.
Opening it, she found another smaller book. Looking at its spine, all it said was "Diary."
Her eyes widened. Her father must have gotten it as an extra birthday present! She looked inside and saw it was completely blank. With a smile, she opened it to the first page and wrote: "This is the Diary of Ginny Weasley!"
Suddenly, below her first line some words started forming: "Hello, Ginny Weasley. My name is Marak."
Her eyes widened. Her Diary answered her! Startled, she pulled back and knocked the book away. She looked at it for a long moment and then went to pick it up. She noticed something immediately: Instead of the spine saying Diary, it said, "Ginny Weasley."
She cautiously picked up the book and opened it again. She immediately saw that the words she had written were still there – as was the answer.
Cautious, she wrote another line. "What is this? How does it work?"
"This book is enchanted so that I can answer you and help you along as best I can. As far as how it works, it is very complicated."
"So you can give me advice when I ask for it?"
"Yes, that's right. Now, before you write anything else down I must as a few questions. First, how old are you?"
"I am eleven years old."
"Are your parents Magical?"
"My parents are Pureblood. You don't believe in all that Pureblood nonsense, do you?"
"No I am not into the pureblood beliefs. My reason for asking is that you should ensure your parents check my magic to ensure it is not harmful to you. As a wise man once said: 'Never trust anything that acts alive if you can't see where it keeps its brain'."
"My father always says that."
"Then your father is a wise man. And to answer where my 'brain' is, it is within the cover and sealed away. This book is very much like a magical portrait. It knows no more than the wizard it was enchanted by. Now, before you take this to your father, you must give permission for your father to read it before he can see what I write or even what you write."
"Why do I have to give him permission?"
"This is because I am YOUR Diary. Everyone should have some privacy. I would never compromise the private thoughts of my owner. And so, no one who isn't given permission can see what is written."
"That is awesome!"
"Yes. It is awesome. Now, take me to your father and let him get me checked out."
"Okay. He has my permission to read you."
Ginny waited until after dinner to talk to her father. Being that her crush was at the dinner table it was very hard for her to talk. And so, when dinner was done, Ginny followed Arthur Weasley out to the shed.
"Dad?" She asked quietly. "I need you to do something, please."
"Hello, Ginny. What can I help you with?" Arthur asked kindly.
She produced the small book and said, "This was in my books when I came back from Diagon Alley. Did you buy it?"
Arthur looked at it curiously. "No. I don't remember it."
Ginny was surprised. "Well, I thought it was an extra birthday present. It was an empty Diary. When I wrote in it, it answered!"
Arthur was suddenly very serious. "That's strange."
"I know! It explained that it was like a magical portrait. It said that I should get my father to check out the magic as it reminded me that I should never trust anything that thinks if I don't know where its brains are."
Arthur chuckled at that, despite his seriousness. That was something that he had always taught his children. "Let me see it then."
He took it from Ginny and looked it over. He immediately saw the name "Ginny Weasley" on the side. "Did it come that way?"
"No. As soon as I wrote my name, it changed from 'Diary' to that."
Arthur nodded and opened it. It was blank. "There's nothing written here."
"It said you could read it if I gave permission." She thought for a moment. "Write in it that you're my father."
Arthur quickly got a quill and wrote in the book, "This is Arthur Weasley, Ginny's Father."
His eyes widened as it wrote back, "Have Ginny write that you are really her father."
Arthur did so and Ginny confirmed it. The two watched in fascination as the writing moved down below the suddenly visible earlier passages. Arthur could then see everything that had been written.
"That's a very fancy enchantment!" Arthur knew many diagnostic charms because of his job. And, as the book had said, it came back with the reading of a magical portrait. He did another diagnostic spell and found no Dark magic taint whatsoever. He looked at the book and told his daughter, "It does register as a magical portrait. I've never seen that in a book before."
Ginny smiled in relief. "So can I keep it?"
Arthur considered that. "I'm going to tentatively say yes. But I'm going to also ask a few people I know if they've ever heard about such a thing. While the book is correct and you should be able to have privacy, I will want to see what it says after you've used it for a week. I want to make certain it is not giving you advice which is harmful." He smiled at his daughter. "I love you, Pumpkin, and I don't want to see you hurt."
Ginny blushed. "Don't call me that! Harry Potter might hear!"
Arthur tried to look serious as he said, "I've called you that since your mum and I brought you home as a baby and your hair was so obviously bright just like a fresh pumpkin. But if it bothers you so much …."
"I don't want Harry Potter to hear I have such a baby-like nickname!" Ginny was horrified.
Arthur looked at her with affection. "You'll just have to live with it. When you're a Grandmother yourself and if I am still around, I'll probably still call you Pumpkin."
Blushing, Ginny mumbled under her breath and, grabbing her Diary, ran off. Arthur waited until she was inside. He then let out his loudest laugh of the summer. His children, at times, were quite amusing.
He then went inside to talk to his wife and let her know about the Diary.
All throughout the year, and for the remainder of her time at Hogwarts, she regularly wrote in her Diary. And while it always gave helpful advice, she didn't always listen. Unfortunately, when she ignored the advice, things normally went badly. And so, she didn't do it too often.
After she got married, she out grew the need for a friend and confident who wasn't her husband and wrote in the Diary that she would no longer be asking for advice.
It congratulated her and explained how to copy its contents to a new book. It then explained that she could now give it to one of her children and that it could provide companionship and advice to the next generation.
And so, the Diary was passed from Generation to Generation within the family. And while no one knew exactly who had enchanted it, they had all been thankful for a loyal friend who was there at the darkest and most embarrassing of times.
Along with the Diary was a whole collection of the Diaries of those who had gone before. The collection was known as the Marak Collection and it was highly prized by those who inherited it.