I take a sleep intermission every night. Get up for a few moments, use the ladies' room, sip a little water, give the kitties a snack. This is how I discovered the raccoon, but that's another story.
Every night when I return to bed, my dear husband has taken the shape of his container; i.e., there is no room left for me. And he steals the blankets while he's at it! Sometimes, if Luna Cat has not gotten up with me, she takes over the remaining bit of warm bed and lies there, dead asleep and much heavier than she is by daylight, like a rock-cat.
So I crawl in and squeeze myself into little sphere with one foot diameter, carving out a small space to use as my base of operations. Then, I yank some covers on to keep from freezing. Cat and husband groan in response, and sometimes I even get a muttered, supremely irritated, sleep-talking "Come on" from the human. Once securely in the bed, I began my expansion. I start by pushing the cat with my feet. This doesn't always work, so I have to shake her a little and call her name, which usually gets another irritated sleep-sound from husband.
Once I uproot the feline, I must shove the human from the center of the bed back to his side. Usually I accomplish this by lying on my side facing him and pressing my knees into either his kidneys or his knees, depending on whether he's sleeping on his right or left side. This gets a big "Harumph" and a dramatic flop as he rolls over and cedes my bed-territory.
5 months ago