This is so wrong.

Alex removed his mouth from hers, placing kisses along her jawline and finally resting at her neck, sucking on that one spot that made her squirm.

But why does it feel so good?

“Alex…” she breathed. He hummed into her neck, the vibrations shooting sparks through her.

Jack paced around his apartment, letters in hand. Should he trust this anonymous sender? Whoever it was had really plucked that one nerve he hoped would never bother him again.
“What the fuck am I supposed to do?” he asked to his empty apartment.

I need to speak to Alex.

And off he went. He made his way to his car, making sure he had the spare key to Alex’s place. He needed to ask Alex what these letters meant. He just hoped his fears were not confirmed. He was nervous. What if this was someone playing with him? What if Amy thought Jack was being ridiculous and paranoid again? His knuckles turned white as he gripped the steering wheel. He sat behind the driver’s seat, parked up outside Alex’s apartment. He sighed, before making his way out of the car and towards his best friend’s front door. He was not prepared for the noise that greeted him when he opened the door.

“Alex” Amy called out once more, this time with more control of her voice. However, in his drunken state, Alex simply moved his lips to her collarbone and his hands slid underneath her t-shirt and ghosted over her hips.
“Alex, seriously!” she placed her hands on his shoulders, pushing him away. He looked at her completely dumbfounded.
“We-we can’t be doing this. This isn’t right” she almost whispered avoiding his gaze.
“What would Jack think?” she sighed, a huge pang of guilt hitting her right in the gut. She was disgusted at what she had done.
“WHAT WOULD JACK THINK OF WHAT?” the pair almost jumped out of their skin as the door slammed open, hitting the wall with a loud bang. Amy paled at the sight of her boyfriend standing before her, in bed, with none other than Alex Gaskarth above her. His best friend and his girlfriend, hell, the love of his life, both in bed with each other. Jack was livid. Seething. Once again, his knuckles turning white as he stood staring at the pair, hands balled into fists at his sides.
“Jack” Alex began scrambling off the bed.
“Save it, Gaskarth!” Jack snapped.
“Care to tell me what the fuck is going on?” he asked through gritted teeth.
“J-Jack, honestly... it-it’s nothing!” Amy frantically tried to climb off the bed. Her hands were shaking. She had been caught and there were no two ways about it.
“Nothing? NOTHING? Mind telling me why I walk into my best friends’ house and I’m greeted by the sound of my fucking girlfriend moaning his name?!” he was past the point of angry. He could feel his blood boiling. He was almost certain that if this was a cartoon, steam would be pouring from his ears.
“You know; I didn’t want to believe it. I really didn’t. But here I am witnessing my girlfriend cheating on me with my best friend!”
“YOU!” He shouted pointing at Alex. He quickly made his way over to Alex as Amy ran and stood between them.
“D-don’t hurt him! It was all my fault” Amy sobbed.
“I’m the one who came to him for comfort. It was stupid. We’d had too much to drink and-“ a sob choked its way through Amy’s throat, her hands moving to hold her head as she broke down completely.
“W-we just kissed, nothing else” Alex spoke, his voice shaking. He had never seen his friend in such a state as Jack was now.
“Please Jack” Amy said, reaching out to touch him in the fear that he would just disappear right in front of her.
“Don’t!” Jack snapped, pulling away from her. Amy flinched as Jack, strangely enough, let out a chuckle.
“I should’ve known this was happening behind my back” he laughed lightly as he looked at the floor.
“I’d been warned; I just didn’t want to believe it” he smiled.
“Jack please, just let me come home with you, we can sort things out. Please” Amy begged. Jack just laughed again.
“Home? You mean that home full of lies? Every time you told me you loved me, I actually fell for it. Well Alex, you were right. I know you’ve always called me an idiot, but I didn’t actually believe it till now” he laughed again.
“I hope you two have a wonderful life together. Oh, and spare the wedding invitation. I won’t come” Jack smiled as he began to walk out of the room.
“JACK!” Amy called, running after him and grabbing his arm.
“What are you saying?” she said, tears streaming down her face. She looked up into those eyes. Those brown orbs that she had been lost in so many times before. Her heart shattered at how hollow they looked. They weren’t full of love like they normally were. They were now black pools of nothing. Emptiness. A broken man.
“I can’t do this anymore, Amy”
“We’re done. Finished. Goodbye” and with that, Jack left.

Notes

I couldn't help myself and got carried away