Barnaby blinked at the key Kotetsu had just handed to him. "What's this?"

"A spare key to my apartment."

Barnaby's heart did something unhealthy. "That is ridiculous. Why would I need a key to your apartment?"

Kotetsu shrugged. "You're my partner, you should have a way to get in if you need to, or if something happens. Maybe I get locked out, or something else, I don't know! It's in case of emergencies."

"I still think it's ridiculous," Barnaby said, but he pocketed the key anyway.