When I was a child, I was always terrified that there might be a monster under my bed. Thus, I spent much of my childhood tucked firmly into the covers lest the monster seize an exposed arm or leg. I don't know what I thought the monster might actually do if it grabbed a limb, but it seemed like a risk I wasn't willing to take.
This morning I was sleeping comfortably with one arm dangling over the edge of the bed when suddenly a creature seized my hand in its claws and began biting my fingers. Because I am a grownup, this caused me to wake up only slightly annoyed rather than terror-stricken.
I took it as a hint that Trillian was ready to get up, so now we're hanging out in my office while I decide what to have for breakfast.