Adrian Tchaikovsky has a pretty good, playful line in non-human characters. My favourites of his are probably the ravens from Children of Memory, who aren't called Thought and Memory, but could be.

As with his cetaceans from Children of Ruin, they have a split consciousness. In the birds' case, one bird in a pair has something like the executive function, while the other has the power of noticing. They can only function by working together. In the case of the cetaceans, the brain/head does the emotions and executive stuff. The tentacles have mechanical intelligence and follow through on the wishes of the being at their centre.