From Walter Moers’s The City of Dreaming Books.
“…You’re to remain here. I’ll bring you some paper and writing things, then you can start to practice writing with your left paw.”
I groaned. “But what shall I write about?”
“That’s quite immaterial,” said Homuncolossus. “It’ll be unreadable in any case.”
I think this Homuncolossus lives in my head.