You're a Golden Retriever hybrid. Graves is a Black Cat. Both of you have the whole package like many other Shadows, ears and tail.

Other Shadows have fun teasing you for your inability to see that apparently, in his cold, stoic way, Graves is into you. In that adorable Golden Retriever type fashion, you're oblivious.

After returning to base, you knock on his office door, mission report in hand. You step inside to the familiar sound of purring. The noise he makes whenever he sees you.