The Knights of Arthur

"The Knights of Arthur" (1958) is a science fiction story by Frederik Pohl about a strange being and its human servants.

Excerpt:
I locked the door of the hotel room. Arthur was peeping out of the suitcase at me. I said: "I'm back. I got your typewriter." He waved his eye at me.

I took out the little kit of electricians' tools I carried, tipped the typewriter on its back and began sorting out leads. It was a slow and dull job. I didn't have to worry about which solenoid lead went to which strand - Arthur could sort them out. But all the same it took an hour, pretty near, and I was getting hungry by the time I got the last connection taped. I shifted the typewriter so that both Arthur and I could see it, rolled in a sheet of paper and hooked the cable to Arthur's receptors.

Nothing happened.

"Oh," I said. "Excuse me, Arthur. I forgot to plug it in." I found a wall socket. The typewriter began to hum and then it started to rattle and type.