I still find it hard to believe. That you can draw on someone's face, while they are sleeping. Instead of drawing on their face, you should have checked them for vital signs.
I've seen this occur many times and the idea that the subject is alcohol poisoning level drunk is inaccurate. Not only that, but it is actually generally very common for the subject to wake up during the procedure, but be so dim witted by the alcohol that they look at the 5 people huddled around them holding pens, focus a few times and then go right back to sleep.
The last time that I recall we did it, the poor fucker woke up in the morning, realised what had happened and announced that he had to be at work in an hour (working a toll booth in a car park). He could not get the pen off so as far as I know, some people got let into a carpark by a pirate with a very red face from scrubbing attempts.