Why is a cat better in a bed than hot water bottle

I have a cat. She is an orange and white. I think she is the best cat in the World. When I lay down in my bed she crawls there, purrs, and she keeps me warm. I do not have to heat water on the stove and carefully fill a bottle with scalding water. Then I have to plug the bottle well so the water will not spill into my bed (it already happened) and wait until the bottle will be hot just enough to warm up my feet. Then I have kick the bottle out of the bed when the bottle gets cold. This procedure is possible to repeat several times during the night. It is very different with the cat. She purrs, it means she is happy to be with me and keeps me warm whole night. When she lulls me to sleep, she gets out off my bed and she does what the cats do. I do not disturb her. Sometimes, during the night, I feel warm heat on my back. The cat sleeps there. Copyright (c) Marie Neumann Translated from Czech Pottsville, Fall 2010