Sevasey One Shot

Jealousy

Summary:
Casey had an old friend, an ex who came back to Chicago, joined the CFD and got placed at 51 as a candidate. Casey and Severide's relationship had just gone from friends to boyfriends, and they are in the honeymoon phase of their relationship. They have yet to come out to anyone, so it's a secret anywhere outside their shared loft.

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Severide woke out a few minutes before his alarm would go off, and he quickly turned it off and looked down. There he was met with a sight of blonde hair that belonged to his boyfriend. Matthew Casey. They had just started dating, and it was still really new. It was only two weeks of being officially together, but it felt right because of their long-term friendship.

The first few days were awkward, to say the least, because neither of them was openly into boys. It was an adjustment but something that didn't take longer than a day to adjust to. They had confessed their prolonged-lasting feelings towards each other after a drunken night where Severide had caught Casey making out with some brunette at a club they went to, just the two of them. Severide was drunk enough just to scare the brunette off and got all possessive of Casey. He had pulled Casey out of the club and stormed back to their loft with a confused and tipsy Casey barely keeping up. The second they had gotten into the loft, Kelly had Casey pinned to the closed door and kissed the air out of his lungs before growling 'mine' and attacking Casey's neck. He was letting some of the pent-up sexual frustration that had built up over the years take over as he sucked a big Hickie right on Casey's neck where everyone would see. Casey was confused, hot, horny, drunk and relieved all at the same time that it was too much for his drunken brain to handle.

Luckily nothing happened further than a heavily make-out session and more hickeys on each other's necks before they had composed themselves and made a coffee. After they had sobered up a bit more to the point where they were more coherent, they talked.

Casey had confessed that he had liked Kelly ever since the academy but never acted on it for two reasons. One, he didn't know if he was even into guys, and he wasn't out himself but knew he was bisexual. Two, he wasn't the type for casual hookups and liked to know the person before getting serious, and Kelly had given the vibe of doing one-night stands more often than a committed relationship.

When the two of them and Andy had gotten closer and become a tight group of friends, risk ruining that friendship was not something he was willing to give up. Matt didn't have a steady support system growing up since he lived in an abusive house and was in the system for his whole teens. He barely had anyone who was a constant in his life, some he could rely on, and Andy and Kelly seemed to prove that they were there for him. He couldn't risk losing something he had longed for all his life, so he pushed his feelings away. When Andy died, and after they had made up their friendship, it only confirmed to Casey that he really couldn't act on these feelings for Kelly. Kelly was the only one who felt that is still a constant despite their arguments here and there.

After a while, the feelings were easy to ignore, especially when he had other people to distract him but deep down, he knew that Kelly was always there. Kelly was always in the back of his mind. Back of heart.

For Kelly, the first time he felt something for Matthew Casey was when he saw him in action. When the three friends got placed in the same house after the Academy and Kelly got to see Casey in action for the first time only made him realize how great of a person Matt is. He saw how Matt could put that aside and focus on the task at hand no matter what was going on in his personal life. He truly cared deeply for the victims and always checked in at the hospital and asked a nurse how they were doing to make sure. He saw how Matt had everyone's back and was fearless. He knew all these things about his best friend but seeing it in front of his eyes was a whole new experience. He felt in a trance by him, and at first, he thought it was just platonic admiration for Matt on the job, but he found himself doing it more and more outside of the firehouse.