Keys with blue fox charm found near Reading Terminal Market

I found a set of keys this afternoon around 3:15 pm near Reading Terminal Market on Market Street in Philadelphia. They’re on a brushed-nickel ring with about seven keys and a bright blue silicone fox charm attached. One key has a small red heart sticker on the handle, and there’s a tiny black USB drive clipped to the ring. The fox charm is easy to spot, and the keys look recently used but in decent condition. If anyone recognizes them, I’d be happy to return them to the owner; they seemed important and I’d hate for someone to be without their stuff.