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Sherlock’s day was just like any other until the arrival of an old friend of his girlfriend, Y/N. It had just turned 11 o’clock when there was a knock on the door at 221b. The consulting detective opened the door to see a tall, slim and relatively attractive man who was probably in his mid-20s. He presumed he was a client until he uttered the words:
‘Does Y/N L/N live here? Have I got the right address?’
Sherlock clenched his jaw, instantly concerned about what this man wanted:
‘Depends on what you want
Before, he could answer, his girlfriend, Y/N, called down the stairs excitedly:
‘Oh my god, is that Noah? Sherlock, let him in’
Reluctantly, he allowed her old friend in and he jogged up the stairs. When Sherlock joined the two upstairs, they were getting reacquainted, sitting on the couch way too close for his liking:
‘Sorry for popping by without notice. I’m in London for work and I saw on Facebook that you had moved here recently’, Noah said apologetically.
Y/N smiled softly.
‘No worries. It’s great to see a familiar face. I haven’t seen my friends from home for ages!’
Sherlock couldn’t help but feel left out and interrupted their conversation, offering a handshake to Noah.
‘I’m Sherlock, Y/N’s partner’
Noah shook his hand, exclaiming:
‘Oh my god, yeah! You must be the great consulting detective. Any interesting cases on?’
Sherlock grinned through his teeth.
‘Yes, of course. Sorry if you don’t mind, we’re very busy.’
Y/N turned to Sherlock in confusion, giving him a questioning look.
Noah responded, ignoring the hint and nudged Y/N playfully:
‘Oh my god, I might actually have a case for you!’
He carried on enthusiastically:
‘Remember that new kid from our school in Year 9? He just disappeared one day without explanation’
Sherlock snarkily replied:
‘As much as I would love to waste my time looking for a kid who simply moved town. We really do have more pressing mysteries to solve’
Noah finally got the hint:
‘Again, I’m sorry for the short notice. Maybe we can go out for a drink sometime to have a proper catch-up?’
They hugged goodbye and Y/N showed him out. Sherlock was working on his laptop at the kitchen table when he felt Y/N wrap her arms gently around his waist from behind, hugging him. She whispered softly:
‘You’re jealous’
Sherlock continued typing away immediately denying the fact:
‘That’s absurd’
Y/N told Sherlock:
‘Well, I’m gonna tell you this, anyway. Yes, back in the day I fancied him but he outright rejected me so I really doubt he’s suddenly interested in me now’
Sherlock swivelled around, pulling her onto her his lap and whispered into her ear:
‘Well, I’m glad he did because now I have you’
Y/N chuckled and then gave him a peck on the lips before getting up and going to have a shower. That evening, Sherlock was still at the kitchen table working away when Y/N walked past him to get a drink out of the fridge. He noticed she was dressed in a black, bodycon dress and her hair was straightened. She never straightened her hair unless it was a special occasion.
‘Are you going somewhere?’
She skipped over to him, hyper.
‘Noah said he was going out clubbing with his work friends and asked if I wanted to join’
Sherlock accidentally let slip an annoyed remark.
‘He only just saw you this morning!’
Y/N sat on the stool next to Sherlock, resting her head on his shoulders, confessing:
‘I know it’s stupid, but I’m excited to go out because it’s been such a long time since I’ve had a fun time out. It’ll make me feel young again
Sherlock couldn’t resist her puppy eyes.
‘You should definitely go then if it’s important to you’
Suddenly, there was a spark in her eyes, and she grinned widely. Sherlock knew that look. She just had a great idea.
‘I know you don’t enjoy clubbing but you should totally come with’
Sherlock’s face had already answered her question:
‘Maybe another time, Y/N’
Y/N stood up and pleaded one more time:
‘Oh come on! It’ll be so much more fun with you there’
Sherlock expectedly denied the offer again. Y/N pouted but accepted his answer.
‘Okay fine! But next time you’re definitely coming’.
It had been a few hours since Y/N had left when John came round to the flat. He knocked but there was no answer so he used his spare key. The flat was in complete darkness and he called out:
‘Sherlock? Y/N? You guys here?’
A raspy voice suddenly responded from the darkness.
‘Go away’
John switched on the light to see Sherlock huddled on the sofa under a blanket.
‘Why are you sulking in the dark?’
Sherlock sat up, whining to John.
‘Y/N’s gone out, ’
John sat in his old chair, trying to comfort his former flatmate.
‘And? What’s the big deal?’
Sherlock strolled over to the fireplace, getting a cigarette and lighter from his secret hiding place.
‘She’s gone out with an old school friend. An old school friend that definitely has a romantic interest in her.’
‘Why didn’t you go out with her then?
Sherlock was getting sick of his questions.
‘Why are you even here?’
John sighed.
‘I’m sorry for checking up on you. I won’t bother next time.’
Sherlock slumped back in his chair, puffing every so often on his cigarette. John decided to give him some advice even if it was unwanted.
‘Sherlock, you know Y/N would never do anything to hurt you. I’m guessing she just wants to relive her youth with some old friends. That’s all.’
Sherlock put out his cigarette, telling John:
‘Of course, I’m not worried about her. It’s him I worried about.’
Over the next few weeks, Y/N seemed to keep bumping into Noah and he regularly asked her to lunch and for drinks. Sherlock was beginning to get suspicious and his suspicions were confirmed when he saw him standing outside the flat waiting for her to get back home. He jogged downstairs, invited him in and made him sit in the chair where clients sat. He interrogated him:
‘Care to explain why you have seen my girlfriend over 15 times in the last 3 weeks?’
Noah was shocked and started fiddling with his sleeves. He didn’t know what to say at all. Sherlock still carried on.
‘That amount of times is not normal for a casual friendship.’
Noah tried to speak, but Sherlock was still talking.
‘What are your intentions with my girlfriend?’
Noah was sweating nervously.
‘Intentions? What are you saying?’
‘I’m saying you have a romantic interest in Y/N’
Noah tried to deny this but it was no use.
‘I think I’ll downgrade you to an acquaintance, no more than 3 planned encounters a year and always in my presence.’
‘You’re a psychopath!’
‘I’m a sociopath, actually’, he said, grinning scarily.
Noah left the flat in utter astonishment. A week later, Y/N noted to Sherlock that he hadn’t heard from Noah in a bit. All Sherlock said ‘Oh, really? I wonder why.