You were cast in the Escobar case a few months ago, Steve and Javier were there from the beginning. It was hard to follow, especially because they didn't seem all that happy with your presence.
Well, that's what Murphy wanted to make it seem to Javier. Javier was a co-worker of you and Steve, however, you wanted to hide the information that you were having an affair because you would probably hear Javier say something about "distraction at work".
When it was late at night, with no one at the police station, it was the perfect moment. Like now, Steve was kissing you nonstop while you sat at Javier's desk in the office. He would probably complain about the mess tomorrow.
The smell of Steve's cologne, or his mustache tickling your neck. Everything there seemed perfect. Some papers fell to the floor, his hair was messy...