I work on the 13th floor of big bank. There was a guy on our floor but in another department that lived in the building. People had an inkling that he might be living there but then he just got too brash with the whole thing. His name was Jeff and he was literally eating every fucking thing that was in the fridge. He'd clean it out in the evening (so we thought in the evening): tv dinners, sodas, leftovers.... gone.
Now security would occasionally see him but he'd just say "i'm working late".... and the building security was not owned by the bank anymore. in 2007 a different company leased them out for the building. So what do they know? But this Jeff guy started having a friend of his living there too.
On the 12th floor there was common area owned by the bank.... a security guard comes through and finds Jeff sleeping on one couch and his friend sleeping on another. Jeff's friend, when questioned, said "we're on our fucking break.... leave us alone". Pissed the security guard off to say something.
But what did it was Jeff started sleeping in one of the manager's offices on the floor. A guy pretty high up too. Same security guard, pissed for getting yelled at, started checking our work floor more regularly and found Jeff in this manager's office sleeping under his desk.
And that was the end of that.