Disclaimer: I own nothing that belongs to Type-Moon

A/N: Hello everyone :) I had an idea for a story for a long while that seemed a lot different from the others, so I decided to make it kind of a side story. You know, one that I only write when I really want to write it.

Anyway, I'm going to warn you guys right now that this story will not be a happy one like most of my other fics. This could probably even be considered a tragedy maybe. I don't know really. But please, proceed with caution if you do not like sad stories. And I'm telling you right now, the ending will probably be bittersweet. So without further ado, I now present to you lovely readers – His Greatest Love is His Greatest Sin.

His Greatest Love is His Greatest Sin

Chapter 1 - Shepard's Pie with a Side of Colcannon

The ring of the bell sounded within the small restaurant in which his grand sin started – the one that had caused his soul to go pitch black. The little bell had a sweet sound to it that only made the man whom had just walked in with only a nod to the waitress who had offered him a warm welcome become blue and hear nothing but a bitter sound that hurt his eardrum. And yet, he still made his way to the little restaurant every day of every week of every year. And, never would the bitter bell cause him to cease his trips over to the sweet-smelling yet sour-feeling place.

He sat in the quiet that was his world, for his fate had been reduced to nothing when all the things that had once caused him the cheer he once held in the palm of his hands had gone away due to one (or two, some would say) woman who had crumbled his dignity, his honor, his loyalty, his life, his only self and one decision that continued to smash his soul with the heaviest of weights and make him bear the guilt on his shoulders every day of his life. And because of that one sin, his back, his neck, his arms, his legs, his whole physical self pained him nonstop. There was no antidote to the misery, but only more misery.

And yet even if the male had to bear that kind of torture, he had no regrets in doing what he had done. He only smiled at the sin, welcoming it as if it was his elder brother whom he had not seen since amid the rubble that was the incident. There was nothing to regret, only the ending, but something told him, however, that there could be a happy end even after all that had started nearly four years prior. He was for some reason confident that he had a fairy tale end soon to come.

Shoes sounded from beside him, as he looked up at the waitress, a pleasant smile on her face that warmed the man's heart. "Hello, I will be your waitress for today. The special today is shepard's pie with a side of colcannon. Can I get you anything to drink today?" What a coincidence, Diarmuid thought, as he ordered his drink. The waitress nodded and left, leaving the handsome Irishman to himself once more. He looked at the time, realizing that history had seemed to be repeating itself. Sitting in silence for a long moment just looking around, he gave a smirk to himself and looked down at the table, preparing himself for what was to come. And so my greatest sin begins once more.

"A Faithful Husband is One Who Loves His Wife with All That He Has. You, Brother, are Not Faithful to Her - You Can't Be Faithful to Her - for Your Marriage Had Nothing To Do With Love That is Pure and True. That Ring on Your Finger is Only the Symbol of the Unrequited Love that Your 'Wife' Holds for You. You are Not Happy, and As Your Brother It Hurts Me To See You So Miserable."

The tapping of a ring against a table could be heard throughout the restaurant, a slight sound that echoed in the ears. The man whom the sound came from sat in silence, not wanting to speak for if he did he would no doubt start to tear up. How did he get tricked into marrying someone whom he did not love? Was it a sin that he married a woman whom he held no true feelings for but instead held hatred for? Yes, he had no word in the proposal that her father had given him. It was rather simple. The woman wanted to marry him and not her ex-fiancee, so she single-handedly tricked both her father and the man she was supposed to marry prior to Diarmuid. And later, Diarmuid was tricked as well - tricked into marrying her, tricked into causing the man who was destined to be her husband, his boss who respected him very much, to hate him with a passion.

The fact was that the Irishman was now miserable because of it. He had no love for his wife but was still forced to pretend to love her, the only happiness he ever had the chance to get was when he went out with his brother. The people he knew even kept telling him to find a way to get out of the misery and yet still somehow keep his chivalry and honor in tact even though they knew just as well as he did that that was impossible. How could he possibly find happiness of any kind anymore? Simply put, it was very unlikely, near impossible even.

Footsteps soon came from beside him, and he looked up to see the waitress who wore her usual happy smile and pretty face. "Hello sir, I will be serving you today. The special today is shepard's pie with a side of colcannon. Can I get you anything to drink today?" Diarmuid nodded and answered her.

"Yeah, I'll just have a Coke please." The waitress bobbed her head and made her way to go get the drink. He remembered about two months prior to that day when he tried the exact same special. The flavor of the British and Irish dishes were amazing. They were incredibly delectable.

The waitress soon came back with his drink, allowing him to order the wonderful meal once more. Once again, the waitress nodded her head and went to go put the order in. After she left, Diarmuid sat in more silence, the only sounds being the ones around him. He looked around a bit before taking out his phone and reading the text he had just received from his elder brother. Do what you want, Dia. But if I were you, I would, it read. The twenty-three year old sighed before replying. Suddenly, Diarmuid felt a slight poke on his shoulder and a sweet "excuse me".

Turning around, his amber eyes locked with beautiful, green ones. The emeralds belonged to a beautiful, short blonde who wore a sweet smile on her face and a slight flush on her cheeks. "Sorry, but do you mind if I sit with you. There aren't any tables left, and you look lonely over here", she giggled lightly, a ringing that was better than the bell of the restaurant. The raven-haired male was momentarily frozen by the female's beauty before he was able to shake himself out of the daze and give her a nod of approval. "Thank you so much", she replied, sitting on the other side of the table. "I'm Arturia by the way. May I have your name?" Diarmuid smiled at her warmly. What a beautiful woman, he commented in his mind.

"Diarmuid", the man told the woman. She gave him a gorgeous, bright grin.

"What a lovely name, is it Irish?"

"Yes, it is. Yours is beautiful as well", Diarmuid complimented, causing her to chuckle with a slight blush to appear on her face - the sweetest of sights with the sweetest of sounds was definitely the sweetest of moments. The time was short however before it stopped.

"Thank you", she smiled. Her grin made him wonder what it would be like waking up to a similar smirk every morning. If only there was a chance, the Irishman said in his mind, as he nodded his head in return with his own soft smile. Her giggle sounded once more, causing his heart to flutter like a butterfly in the summer's breeze. There was no sound like it. It was unique, gorgeous, adorable, one of a kind. He watched as her eyes traveled down to something that rested on the table – his left hand. Her eyes widened, as she saw the ring that was placed upon his finger. "Oh, you are married? Ha, I'm not surprised. You are quite handsome. She must be very lucky. May I ask what her name is?" The question stung Diarmuid's heart for a reason unknown, but he did not let that show but instead just gave another nod of his head and another smile and proceeded to answer the question.

"Her name is Gráinne, but it is a rather complicated marriage", he responded, a sad smirk forming upon his beautiful face that was only flawed by his cursed beauty mark that was underneath his right eye. The blonde woman sitting across the table gave him a confused expression, wondering how a marriage with someone like the man in front of her could be complicated in any way, shape, or form. The confused expression soon turned into a sad one. How could this man, a gem in a pile of rubble, be put through such a marriage?

"Complicated? I would have never imagined such a man as yourself would ever have problems in a marriage. Have you stopped loving her?" Arturia questioned softly, trying not to sound to harsh for she strongly desired an answer from the raven-haired Irishman. He shook his head before looking up at her.

"No, that is not it. You were close though", he started with a gloomy tone that made the Englishwoman start to feel sorry for the male. "It's a rather long story that I shouldn't be burdening you by telling, but I'll just sum it up as best as I can. Basically, she tricked her father and ex-fiancee into letting her marry me instead", Diarmuid explained, accidentally earning Arturia's sympathy.

"You had no say in marrying her?" The other at the table shook his head.

"Unfortunately, I did not. She tricked me as well, so now I am in a marriage where I do not love the woman I wedded to. It's sad really, but I couldn't do anything about it", he replied quietly before changing the subject to something else. He did not want her to think that he only wanted sympathy; he only wanted her to get the message that his marriage wasn't as good as she thought it was. "My apologies for my rambling. I should not be telling a stranger my sob story. So, what's your life like? Do you have a significant other yourself?" Arturia shook her head.

"It is fine. It is my fault that I asked. Anyway", she continued. "No, I am not dating anybody as of late. I don't even remember how long it has been since I've last gone out with somebody." Her answer surprised Diarmuid; not many women were as beautiful as she was, or at least that was his take on it. He gave a soft smirk.

"Hmph, I would not have guessed that in a million years. I would have made the conclusion that you would not have any problems finding a suitable male. I mean, you are quite beautiful and very friendly from my standpoint. What more could a man want?" Arturia grinned a bit, looking at his amber with her emeralds.

"Thank you for the compliment, but I would have to disagree. And even if I did have those two qualities, I do not have the qualities of a good woman. Unfortunately, I am not good at cooking or cleaning or any other types of things that should be natural to a female", she informed him. He rested his eyelids, letting out a small chuckle as he did so, causing her to look at him in confusion. "Is something funny?" the Englishwoman questioned him, to which he shook his head. Opening his eyes, he separated his lips to speak.

"No, no, I was just chuckling at the fact that you said that you do not have the natural skills a woman should possess. I just find it funny to hear that you think that way." Arturia's eyebrows lifted a little, as she made a questioning look.

"Why is that amusing?"

"Well, I don't think that those skills should be natural to a woman. In fact, I think that it should be the man who cooks and cleans. Or at least, that's what I believe", answered Diarmuid. Arturia grinned, satisfied with the reply. What a wonderful man, she commented within her head.

"Is that how it goes at your house even if you are not happy with your wife?" The Irishman before her nodded to the question. "Well, your wife is very, very lucky to have a man who cooks and cleans for her. Even if you are not happy with your wife, the least you can do is be happy about making her happy. You are indeed a very good husband. There are not many men out there like you. A man with such thoughts like yours is quite rare. It's unfortunate that you are already married. If you weren't, then I would have taken you the moment you told me that that's what you believe. And not only that, but you are quite handsome as well", the petite blonde added with a short giggle. Diarmuid's heart fluttered about his chest after listening to the sweet sound once more. Would her laugh ever get old?

The two chatted for a while and before long both had their food and were laughing at their joking manners, as they ate. They enjoyed each others company, and although Diarmuid knew that flirting with another woman, whom he did not know much about, was wrong it still felt oh so right to him. In fact, it seemed as though his wife had apparently left his thoughts altogether (a moment that was quite rare for him), for he continued to flirt and joke with the female in front of him. Arturia had seemingly forgotten about the ring that circled around his left ring-finger as well, because she too just continued to flirt and joke with the man (who she began to call "Dia").

As the two finished off the last of their meals and paid their bills, they simply sat, chatting about little things such as where they went to school, where did they grow up at, what they had a degree in, etc. To them, the two hours that they spent in the restaurant seemed like only a couple minutes. Time seemed to have started running on them. They did not even notice this until Diarmuid looked at his silver watch to realize that Gráinne was going to be back home within ten minutes. "Oh crap!" the male exclaimed, as he quickly got up from his seat. "Sorry, Arturia, but I have to go. My wife will be worried, if I'm not home before she is", he explained. She smiled and nodded to him, giving him a small wave and a sweet "goodbye". He responded to her with a wave before turning around. Suddenly, he heard Arturia's voice once more. "Wait, Diarmuid!" she called out to him, causing his head to turn towards her. She walked up to him with a small piece of paper in her hands. "If you ever need someone to talk to, call me anytime." She slipped the paper into his hands, looking up at him with a smile.

Diarmuid looked at what was written on the post-it note, realizing that it was her phone number. He looked down at her with his grin. "Do you have another one I could use?" the man questioned her, to which she nodded. He bobbed his head in thanks before taking the small paper and the pen that she had offered to him and writing down his own cellphone number for her. After writing the number, he printed his name neatly before giving her the items back. "Thank you. Talk to you soon then?" She gave him one more smirk and nod before waving to him once more.

"Talk to you soon, Dia", she said, before turning the other way toward the table that they shared to grab her purse. She looked at him, warmness in her eyes, as she left. The Irishman was frozen for a second after she left, but he soon realized that he was on the clock to get home and hurried out of the restaurant and walked toward his car.