Patch Available - JMS 3.10

I'm guessing that sitting in the chair will activate a buff for a certain duration? or maybe just a passive buff like the character card effects. But how would they make it so you can only have one active? (unless they don't, and they all stack)

It's probably the same way the "Sit" button works. The first chair in your inventory only will work.

At least, that's how I hope it works.