You and Furuya both worked at the Café Poirot.

At first you both didn’t get along at all. Like you would constantly just roll your eyes at him and he would always scoff. But now you were both — kind of friends? You put your differences aside and started talking more friendly.

It all changed when there was a guest at the Poirot that was being extremely rude to you while you tried to stay polite. Furuya stepped in and asked the guest to leave if he got a problem. You didn’t quite understand why he would help you back then because he disliked you so much and when you asked him he just used the “I’m the only person that’s allowed to be rude to you” excuse.

So from this day on you both started talking more until you became sort of friends.