It seems, as discovered by Mark Kirby, that Mateo created the room (on June 26th 2012), with the purpose of coordinating voting.
Why would one want to coordinate voting? Well, questions with no answers and a negative score are automatically deleted if they have been around for a while. It's evident from the conversation leading up to the creation of the room ...
You won't find the chat links in user profiles, it is located in the top right on the black bar, in the little stack exchange hamburger "community" menu, it can be a bit hard to find.
It is also located on the footer of every page
Here is a direct link too, just for completeness
Don't worry about it. Inactive rooms are deleted automatically by the system. I don't remember if non-mods can delete the rooms they created, but if you can, it will be on the "Access" tab.
So, try going to https://chat.stackexchange.com/rooms, find your room, click on the "info" link of the room, go to "access" and see if you ...
Related post on Meta SE: How do you delete a room on chat?
Related chat FAQ: Will these rooms exist forever?
Quote (emphasis mine):
Rooms will exist indefinitely, so long as there is at least one person actively talking in the room. A room is considered worth retaining if it has more than 15 messages by at least 2 users.
Rooms not worth retaining which are ...