Unbetaed. I don't own Sherlock Holmes, sadly.
But, well I tried. Tell me what you think and if it seems realistic
P.S. English is not my native language and I apologize for any mistakes I made. A quick feedback in hindsight of the grammar and such things would be appreciated.

He didn't know how it happened, but it happened. Somehow John found himself in the past. His memories of the future intact and himself mostly sane. The doctor – logically – was confused and could not imagine what happened. The last thing he remembered was Sherlock falling to death, his own panic and grief, the burial of his best friend. John tried to contain his grief by working nearly 20 hours a day, until he fell asleep in the staff room, his body driven to exhaustion and his mind replaying the incident.

In his dream he watched his friend fall again and again, the whole time the ex-soldier was torn between cursing Moriarty and – strangely enough – pitying him. In his opinion nobody was born evil but got corrupted through life. And to become such a dark person something horrible had to happen – at least that's what John thought. "Even then, Moriarty could have chosen a different way.", the doctor argued with himself. "But what if he did not know how? If the only methods he was taught where the dark ones?", told he himself. In the end he resigned himself to watching his friend die all over again, while he stood on the pavement and could not move. "If I only could change the past.", he said in his dream, while he watched his friend descend to earth. "You could.", a voice suddenly told him, and the blond man jumped and turned his head towards the voice. There was only darkness, curled around him.

"What?", the ex-solider tried but the voice began to speak again, "You could change the past, if you really wanted to. But if you do that there would be consequences. The biggest one would be that you never could come back to your original timeline. You will live and die in another timeline and the John Hamish Watson that exits now, would never exist. But you could save a lot of people if you chose to." The last sentence convinced John and he didn't say anything else then: "Yes." With a last "Good. So be it.", the darkness overwhelmed him, and the doctor knew no more.

As the man woke, he found himself in a bed and an unknown room. Rolling himself out of the bed and marveling the strange dream he had, he looked out of the window and promptly began to pinch himself. 'I am still sleeping.', was his thought, but as pinching himself did not help, he ran his hand through his hair and sighed deeply. 'What happened?', he asked himself and looked out again. Outside he could see a few trees and what looked like a city, but nothing that reminded him where he was.

Warily he began to search the house and tried to find a clue where he was, but what he found only confused him further. The whole interior looked like it was out of an old magazine, even an old calendar which read the year 1979 hanged somewhere on the wall. Finally, he reached what looked like the kitchen, where a small letter lay. On the envelope stood 'Dr. John Hamish Watson' and he hesitantly opened the envelope, fished out the letter and began to read.

At the end of the letter he was swaying and feeling faint. With weak knees he made his way to the bathroom and looked at himself in the mirror. He still looked like himself, only twenty years younger, which validated the letter. He thought that he was crazy, but then remembered the dream he had. Maybe the dream wasn't that much of a dream. No other explanation could be given how he travelled back in time and was rejuvenated.

And he was definitely rejuvenated since he looked like twenty again, instant of the nearly forty he was used to. If the letter could be believed he was eighteen again, with a doctor license and enough money in his bank account to 'make his journey easier'. Whatever this meant. Looking for his wallet he went through the house again and strangely found it in the kitchen beside the opened letter.

Inside he found his ID, money and a bank card. Deciding that he wanted to know what defines as 'enough money' he went to the bank from the card. While walking there he felt like a tourist. Losing his way and having to ask for directions was humiliating, but in the end, he reached his destination.

Then he went to the nearest open counter and asked to see the total amount of his account. As the banker gave him a slip of paper with so many zeros on it that Johns head began to spin, he decided, that this was more than enough money to life comfortable for many, many years. More like his descendants could still spend a lot of money and never have to work again. At the thought of children, something inside him began to shift and a crazy idea ran through his mind.

And suddenly he knew what to do. What he remembered of Mycroft's and Sherlocks' research he knew that Moriarty lived in an orphanage until he was fifteen, were he then disappeared and only appeared again as a criminal mastermind. He also knew that his mother was a drug addict and he lived with her until social services took him at the age of eight. His father was mostly unknown. The mother could only tell that he was a rich man who paid her a yearly sum to keep her mouth shut and their son away from him. So, he began to plan. He bribed a few people – since he had enough money in his account – to find the mother and a week later he got an address.

With that he took off to the location in Ireland. After he arrived, he noted that was a relatively big town, nearly a small city, with enough people to go unnoticed as a drug addict with a child, but small enough to be not too expensive. John went to the nearest motel and rented himself a room, for a few days, not knowing how long he would need for his mission. He took his luggage into his motel room and fished out a slip of paper. The ex-solider read the address again and began to search, after an hour he admitted defeat and asked a local for directions.

Half an hour later he stood before a small house. From the outside it looked like a small, cozy hut, perfect for a single mother and her child, but the doctor knew that the coin always has to sides. Hesitantly a made his way to the door and raised his arm: 'Gosh, am I really doing this?', he asked himself unsure. A loud noise from the inside brought him back to reality and the small whimpers that could be heard, decided his fate.

The time traveler knocked loudly on the door and the noise from inside quieted. A murmur was heard as a woman's voice told someone, something. What exactly was said, John couldn't hear, but he doubted that it was anything good. A few moments later the door was opened, and a petit woman stood in the doorway. The woman looked sickly thin, her face looked gaunt and overall, she was very pale. Due her short skirt and shirt, the track marks were clearly visible, the woman noticed his stare, crossed her arms, and wanted to know: "Can I help you?"

Shaking himself out of his stupor, the man countered: "The better question is how can I help you?" This left the woman confused, which used the doctor: "May I enter?" Reluctant, but still overwhelmed from the strange man, she let him in.

John looked over her interior and decided that the outside promised more than the inside looked like. It was oblivious that most of the money went inside the veins of the woman then her house. He was quickly led to the living room – or at the least, that's what's supposed to be – where he sat down on one of the worn chairs. The woman sat down on the one across to him and crossed her arms again. "So, what do you want?"

"Your son.", he answered honestly. The woman began to laugh: "Are you stupid? Why would I give you my son? I don't know anything about you, why would I give him to you? You could be a pedophile." The blonde man took out a few papers, which after signing them, would make James 'Jim' Moriarty his son. "I think you will sign these papers because of the money. You simply will not tell his father and still get your yearly fix. And I will pay you a good amount for him." John hated talking like this, but only money could and would go through the woman: "Also I'm not a pedophile, only a man who wants his legacy to go on. Since cannot father children, I would like an extraordinary son and a few people told me your child has the potential to become such a man." He hoped that this lie would be enough for the woman and reached for the bag he had with him.

He shoved the bag over to the woman and instructed her to open it, which she did carefully. After opening it she gasped: "What-?" "This is your compensation for the trouble.", he told her. The woman looked at him in shock and then to the papers, then back to the bag with the money. Making her decision she quickly took the pen, signed the papers, and slid them back to him: "I won't be taking him back.", she informed him, which the ex-solider didn't commend.

Instead he said: "I want to take him with me now, where can I find him?" The woman stood and walked across the room, to a wardrobe which could be locked. John already knew where this was going stopped before and let her unlock it. Inside was a small child, no older than three, who looked miserable and close to tears. The woman walked bag to the bag, took it and with a "Close the door behind you.", went away.

The doctor looked at the huddled figure and began the process of getting him out of the cupboard. "Hello.", he told Jim, "I'm Doctor John Watson. I'm taking you away from here." The black-haired boy looked and seemed to deduce him with his dark eyes. Whatever he saw the time traveler did not knew, but the moment the boy made a decision was clear. He opened his arms and reached for him. Carefully John took him in his arms and marveled how light the boy was.

Deciding to fatten him up when he gets the chance he asked: "Do you have anything you want to take with you?" Moriarty shook his head and with that the doctor took the papers and began to make his way back to the motel where he stayed. "Tonight, we will rest here. Tomorrow I will take you back to my home, there you will get your own room.", he explained James, who looked at him curiously and at the same time distrustful.

As he reached his room, he noticed that he didn't think this through as he didn't have any clothes for the child or something to eat. With a sigh he put the boy in the bathtub and wanted to wash him. Jim however began to struggle and even to bite him, which caused the ex-solider to let the toddler go. "Okay. I won't wash you. But can you clean yourself?", he tried to compromise. Again, he received a distrustful look and finally a nod from the boy. "Good. Then I will get you something to wear and a hot meal." Turning around he made his way to the luggage and began to rummage inside it. He found a small shirt and a towel, which he took to the door to the bathroom. Unsure how to proceed he knocked and said: "A shirt and a towel lay before the door. The shirt will most likely be to big for you, but I hadn't thought about that before, so that's all I can offer now. When we get back tomorrow, we can shop for a few things, but until the that will have to suffice. Now I will go get something to eat for you. Please don't leave the room."

With that he made his way quickly down to the nearby pub and got something to eat for both of them. Nearly twenty minutes later he made his way back. Arriving at their room he found Jim on his stomach reading one of his medical journals. "Food is here.", he announced himself and the boy twitched and tried to put the journal back. "Keep it.", the doctor told James, "I already read it. But if you don't mind me asking, can your read or to you look at the pictures?"

The boy looked at John in wonder and then shook his head: "I can't read.", he told with a small voice, "But I would like to." This brought a small to the lips of the 'young' man: "And I will teach you. Or hire a teacher.", he added with an afterthought, "But now we eat." "Really?", wanted James to know and John laughed: "Sure." With that the small child flung himself towards the doctor and hugged him tightly. "Thank you.", Jim told the blond man. Surprised by the gratefulness the man simply nodded and hugged the boy back.

A few moments later John let go of James and patted his head: "Okay let's eat." Giving the boy his meal, they both began to eat. After eating the black-haired boy became sluggish and obliviously exhausted. Taking what's left John carried the child to the bed and waited for him to fall asleep. After he was sure that Jim was secure, he too went to bed and fell quickly asleep.

The next morning, he woke up and looked to the other bed, where the still sleeping James laid. Feeling relieved the man began to prepare for the day, seeing that the boy was still resting, he quickly made his way to get breakfast. After getting back he saw that his 'son' had woken and gotten himself another of his shirts. Not minding he took out and offered the fresh breakfast. Grateful the boy took the offered food and began to eat.

Soon after that they made their way to the trains where John purchased two tickets and after a few hours they were back in the city, which the doctor began to call 'home' – only after London, of course. He began the tasks of raising a genius child, employing teachers, taking him on study trips and engaging his interests. And quickly began to forget who James 'Jim' Moriarty was, for him there was only his son. The boy he raised. And on his twelfth birthday, James, his boy, came to him and wanted a special present. With tears in his eyes the time traveler arranged everything.

A few days after his twelfth birthday, James Moriarty ceased to exist.

Instead James 'Jim' Watson, was born.

Six years later

James knew why his dad was withdrawing.

Fifteen years ago, his dad decided to adopt him, despite only being 18 years old. Fifteen years ago, his father rescued him from a future full of pain and darkness. Since then he got to know his dad and learned a lot about him, not everything, which annoys him a little bit, since he normally can read people without thinking about it. In all this time his father never dated or went out just to get a 'leg over'. When asked about it, his father told him that there was someone he couldn't forget and going on a date would fell like cheating and betrayal.

And now he had brought home Sherlock, someone who was as clever as he was. Sherlock who only was three years older then he was. Sherlock, the first person which gained his father's interest. Jim knew he should feel disgusted, but after all what his adoptive dad had done for him, he simply wished that he could find happiness. And maybe then his father wouldn't be to hard on him if he introduced Sebastian, who was seven years older than himself.

A loud groan brought him back to reality and he saw his best friend Sherlock beside him. "Your father hates me.", the curly-haired man told him. The black-haired sighed: "He doesn't hate you Sherly." "Don't call me Sherly, Jamsie.", the young man replied annoyed, "And if he doesn't hate me, how else will you explain how he acts around me." That could be his chance to get his friend on the track to his father, but what would Jim do if the other was disgusted? Thinking quickly, he answered: "Why would matter if he hates you? A lot of people do that. And even if he does, he knows me better then to try to forbit me hanging out with you." The black-haired man looked at his best friend and – to his surprise - saw him blushing.

Eyes widening the pieces began to fit: "You like him.", he said stunned. Somehow James never thought that the self-declared sociopath would admit his feelings, even to himself. He thought that he would have to manipulate his friend and father into admitting their feelings. This however made things easier. Getting back to the situation he saw his friend watch him with worry. Seeing this he grinned and teased his friend: "Ohh, does someone has a daddy-kink?"

"Shut up, Jim.", noticing the curly-haired mans discomfort, he became serious: "You like my dad. Admit it." "I won't admit anything." "Well then I won't tell you." Sherlock frowned: "Won't tell me what?" Smirking the black-haired man told him: "Well what I won't tell obviously." The brunet tried to deduce the young man across from him but knew that James won't reveal anything if he didn't want to. Hesitantly he nodded: "Okay, I admit, I may like your father."

Afraid to see disgust in the eyes of his only friend he looked down, only to miss the surprise and happiness flitting across Jim's face. "That's good.", he suddenly heard. "What?", he exclaimed surprised and looked up again. "I said: 'That's good.', because I'm sure my dad also likes you." "What are you talking about? I'm twelve years younger then him. He wouldn't like someone inexperienced like me. Or someone as broken as me." "You're not broken. And I think the inexperience makes it hotter for him. Nobody has tainted you until now. And look how he sees it. He is twelve years older then you and longs to be with you. In the eyes of society, they would damn him, call him a cradle robber. Ask him if he was a pedophile. Or if he pays you. But still I haven't seen my father looks so interested in a person, since I know him, which is like forever. Which I think makes him afraid, so he tries to push you away. Because in his eyes he got nothing to offer you. Maybe money, but since your family is well off, not even that could sway you. So, he tries to push you away and keep his distance."

After his tirade, Sherlock looked thoughtful. James hoped that his friend would make the right decision and he could help achieving his father a little bit of happiness. Even if it was with a man who was twelve years his junior. But in the end Sherlock was better, than some off the high-class woman. Who with their vapid mind, sharp tongues and awful gossip, let even John become homicidal.

"Okay.", his friend nearly whispered, "I want him. Even if he is thirty-three and I'm twenty-one. No matter what others are saying or thinking. If you think I have a chance with him I want to try." Happy with the decision of the brunet, Jim smiled: "Well then leave everything up to me. I have the perfect plan." With that the aspiring detective huddled closer to his friend and listened to him explain his plan.

A few hours later John arrived home and saw a cup of tea and a plate of biscuits standing on the kitchen table. The tea was still warm, and the doctor smiled. His son was often thoughtful and made him a cup of tea when he knew, that John would arrive shortly. After drinking his cup and reading the newspaper, he felt tired and decided a nap would do him good. With that he laid down and went to sleep.

As John began to wake, he noticed that something was different. He tried to move but found himself unable to. The solider took over and he opened his eyes and analyzed the situation: he was in his room; his arms and legs were bound to the bed with thick ropes and he was naked. His clothing was mostly gone, only his pants remained. "What-?", he tried to escape, but it was futile. "Don't try it, dad.", the man heard a voice, which he recognized as his sons. "James, what are you doing?", the doctor wanted to know, but Jim ignored him, the man would get it soon enough. "I want you to know, what ever happens next dad, that I'm completely okay with it. In fact, I even organized it. I only want you to be happy." With that the black-haired man left the room, ignoring the confused shouts of his father.

"He means what he says.", a second voice told the still bound ex-solider. "Sherlock, what-?", the man asked as he recognized the voice of his former best friend and secret crush. Suddenly Sherlock sat on his lap, just as naked as he is.

"What are you doing? Is this some kind of game between the two of you?" "No. I want you. And Jim told me that this feeling is requited." John began to blush and tried to get out of the ropes again: "Sherlock we can't. I'm twelve years older then you. And not just that. What would your parents say?" The curly-haired man bended down and began to kiss the neck of the bound man, who unconsciously drew his head back to offer more to the young man straddling him. "I don't care what they say, or anyone else. I don't care that you are older than me. I only care about you. Please John. Don't reject me. Don't reject us, only for something little as a few numbers."

While he told this Sherlock kissed further down on Johns neck, until he reached the point where it met the shoulder. There he sat up to look the struggling man in the eyes. "John, I love you.", this was his secret weapon, his trump card, as James called it. He saw the moment the doctor made his decision and heard the barley whispered words of "I love you too" Smiling he kissed John and let everything else run its course.

The next morning, he awoke and found himself still in the embrace of John, which let him be grateful that he could call Jim his friend and John his lover. All while John marveled how everything turned out. Jim meanwhile was happy for his best friend and dad and wondered how it would have been if he hadn't been adopted and saved by John. But shrugging these thoughts off, he instead thought how he could snag himself the man he desired and went to plan.

All while fate watched them, happy that everything now stood corrected.