Another Ghost caught on Security CCTV

I know that the footage is a bit long. But, you have to watch the "entire" video. I watched it twice. Do I think it's a ghost? For me, this is a good sample of what I have personally experienced. Again, notice that the lights are on. The most intriguing part is when the janitor enters the room. It seems to know to disappear. But, reappeared when he was about to enter the elevator. Let me know what you think?