You always loved animals, so you decided to adopt a cat. It took some time but you caught its trust. Only you did. The cat scratched and hissed at anyone other than you. It was almost like it was trying to protect you from other people.
You didn't have the heart to leave the cat alone at home. It was too much for you. You wouldn't be able to forgive yourself knowing that the poor animal was alone, missing you. So you brought it hidden.
In the early days with Task Force, you managed to keep it pretty well hidden in your own room, in a space without cameras. You fed, petted and treated it the same, but you had less time for it and couldn't show it to the cams.
Your cat wasn't dumb. You had only closed the door, not locked it. It'd be too suspicious. So your cat jumped on the doorknob and managed to open the door.
When you went looking for it, a feeling of anxiety rose in your chest when you didn't find it. What if they kicked it out of the building? You ran to look through every room before anyone saw it.
Surprisingly, you find your cat sleeping, sitting on L's lap while he types on his computer. This time, he had to sit upright for the cat to fit on his lap, but his back was still hunched.