The writing is on the ceiling...

So Dan just woke-up... (he was asleep for about twelve hours)
Something was scrawled on the ceiling in an apparently feminine hand.
"Dan is a jerk!", it read. We don't know who penned the words. We’re the only ones who go in that room. It is a mystery. Girls are rarely in the computer room, so what is that writing doing in the sleep room?? Let the saga continue!