Here's another one shot, totally unrelated to the first one.
It takes place a few days after Wendy breaks up with Ruzek, not related to what happens in the last episodes of CPD.

Enjoy!

I DO NOT OWN CHICAGO PD NOR ITS CHARACTERS.

When she left

"Ruzek!"

He heard her call him but for a moment he thought it was just it was only in his mind. He hadn't expected Kim to talk to him again after what he told her about really trying to make his relationship with Wendy, his fiancée, work.

He didn't want to be mean and hurt Kim, that was never his intention. But, after all, he was a man of his word and as Olinsky gave him advice about marriage he realized that if he'd asked Wendy to marry him, that meant he must have really loved her. Loved, maybe that was the problem.
So Rebel Without A Cause tried to stay away from his coworker, pretending he didn't have feelings for her. He tried to sound sincere when he told his fiancée he loved her and wanted her, her only. That, for a fact, he knew wasn't true, though: since Adam and Kim's kiss outside the bar, every time he caught a glimpse of her he'd have to fight hard the impulse to go to her and talk to her, touch her, kiss her.
So when Wendy paid him a visit at the precinct to break off the engagement, he was relieved, or kind of. He clearly was disappointed it didn't work, yes, but he was relieved he didn't have to be the one to decide their fate as a couple. He actually appreciated her for having the guts to put a stop to their misery, even if that meant he was the coward. Coward is definitely better than cheater, he found himself thinking and he wanted to punch himself in the face for that, but what else could he think?
The first thing that came through his mind after accepting the fact that he was now single, the only thing he wanted to do, really, was to tell Kim about it. So he went to look for her but found Atwater instead, who reasonably talked him out of it, told him not to bother Burgess anymore, basically saying she was better off without him. But Atwater didn't know the previously engaged man wasn't committed to anyone anymore. He surely also had no idea of how much Adam wanted to punch him in the face for being so protective of her. Atwater was a good friend to Kim, Adam knew, and was grateful for that. However he also knew he was not a bad guy Kim should be protected from.

Adam remained still before Atwater, just as he stood still when he heard her call. He let Burgess approach him and prayed she wouldn't come too near because if she did he wasn't sure he could resist her. He was free to kiss her now, but he wasn't sure the hallway of the precinct was the best place to do it. Not to mention the fact that she was oblivious to what happened between Ruzek and his fiancée so she'd probably think he was crazy. And a cheater.

That word made him shiver. Was he a cheater, for thinking about Kim and practically kissing her back when she naïvely made a move on him? Would telling Wendy all this make him feel better or make her feel worse?
He watched Kim approaching him. She noticed he was unusually quiet. Something must have happened, she thought.

"Ruzek, hi".

"Hey Burgess" she scanned him, looking for something in him that could hint at what it was all about.

"So Atwater said you were looking for me?"

"Yeah he also told me to stay away from you" she looked surprised, but she wasn't, really. Atwater and her had become good friends and she knew he only wanted to protect her. If she didn't know he was married and with a kid, she'd think he had a soft spot for her. Ruzek gestured and indicated the main door "So yeah I think I should follow his-".

"He did?" He nodded "And tell me, since when you do what you're told to?"

She made a point.

"Good point" he flashed her a grin.

"What did you want to tell me? Atwater said you seemed in a hurry" he gently took her wrist, action which caused Kim to look at their hands and back at him confused, and guided her to the stairs to have more privacy.

"Okay, I do not know how to tell you without sounding like a douche".

He hadn't thought about how she would react to the news until that moment. Would she be happy? Upset? Wait, why should she be upset? It was good news. Was it? Maybe it would sound like Hey I'm not getting married anymore so yeah we can have fun without me feeling like a cheater now, was that what she would think?
He had to make sure she knew he was serious about her, that he wasn't just playing around but he actually really cared for her and liked her and didn't want to hurt her in any way. He was even okay with waiting for things to cool off before diving into a new relationship with her, if that's what she thought was best.
Just as he was about to tell her all that, he saw Sergeant Platt give him a nasty look from behind Burgess' shoulders. He shut up.

"You two" Platt said, making sure they knew she was talking to them "Voight's asking about you, go upstairs".
Ruzek and Burgess nodded and went up the stairs. The Sergeant seemed to always interrupt them in the worst possible moment.

Turns out, Voight wanted Burgess to go talk to the wife of a cop, Michael Jones, who ended up in hospital after a shooting. He chose her because he thought she would be able to handle the family well enough. Ruzek's involvement was instead Olinsky's idea, because he believed it would be a great opportunity for him to learn how to deal with that kind of stuff and make him conscious about the risks of their job. It seemed Ruzek was never affected by the horrors he saw, never scared to go undercover or to be in the middle of a gunfight. Except maybe when they involved Kim. In that case, he was always worried something bad would happen to her so he was careful and almost overprotective.

Later that day, Kim was walking down the hallway, ready to go home, when she saw Adam running down the stairs, leaving the Intelligence offices. She called him and waited as he approached her, a smile crooking his lips.

"Hey Burgess, you going home?" he asked as he passed a hand through his ruffled up hair to straighten them a bit. She nodded yes.

"How did today's case end up?"

"The bad guys are going in prison, thanks to you, too" he smirked "and I heard Michael will be out of the hospital soon. He's already doing much better".

"Good to hear. So, you going home, too?"

"Yup. If you wait a second I can give you a lift..." he was suddenly self conscious, thinking maybe she wasn't up for it "If... Of course, if you want me to".

"Okay, no problem".

Kim didn't feel too much comfortable in Ruzek's car. She endlessly wondered why he was so nice and willing to help and be with her, when he was clearly in an established relationship. It wasn't flawless, she'd already guessed they were having troubles – and she hoped they weren't her fault – but which relationship didn't?

Adam had both his hands on the steering wheel and was tapping lightly on it with his fingers. To Kim, he seemed nervous, too, like he had something to say but couldn't decide whether he had to spill the beans or not. By the time he pulled up by her apartment, he'd made up his mind.

"This morning, I was looking for you because I had to tell you a thing" he paused to look at her briefly. He inhaled deep and continued "Wendy left me".

"I knew something was up, but I couldn't imagine this... How are you?"

It surprised her. She was definitely not expecting that and probably neither was he when he was talking to her fiancé. Or should we say, former fiancé now. Se didn't want to think that that made everything between them different. She didn't want to raise her hopes, finally letting herself believe there could be something more, that she could stop trying to forget how good his lips felt on hers that time outside Molly's.

"I'm... I'll be okay. I'm just a bit shaken but, it was probably for the best"

"Let me know, if you need anything..." she glanced at him and put her left hand on his to let him know she really meant it, that she didn't just say it because that's what people felt obliged to say in those circumstances.

"I need a friend. I need you. But..." he told her sincerely "I can't let you be my rebound" He let that sink in, waited long enough for her to understand what he was trying to convey.

"I know"
"So I think we should take it slow, because I know I miss you, and I like you, and I think you like me too but I don't want to hurt you".

"I guess I can wait." she nodded understandingly. They said their goodbyes and he kissed hed cheek lightly. He watched her get out of the car and make it to the stairs to her house, then hopping back down, going back to his car and tapping on the passenger's window. He promptly lowered the window and leaned against the passenger seat.

"Maybe we could start fresh" she extended her hand in order to shake his "Hi, I'm Kim Burgess. Police officer."

"I'm Adam Ruzek. Single." He winked.

Fin.