Cats, one of the many relics left behind by humanity after their fall.
They didn't morph or evolve like many other creatures did, and it's speculated that it's because cats lived too metaphysically close to the heart of humanity (After all, dogs and horses, which are other such creatures much loved by humans, remain entirely unchanged by the Sundering). But cats did experience a change. Their intelligence blossomed and their ability to understand and communicate through speech was greatly enhanced. Cats can speak any language after hearing it spoken for at least an hour, with their level of vocabulary reflecting their experience with a language.
Cats are well known for their lies. Their patron deity is He of the Long Yarn: the Father of Lies, the Bloody Bard, He of the Great Sin. As a result of this connection, cats that can speak are often regarded as unreliable at best or malicious at worst. This reputation, in some places, has been placed even on those cats that cannot speak (as the lineages of those that can and those that cannot have diverged and they cannot intermingle).
Cats seem to have some shared culture, but they neither create nor contribute to any civilization they reside in, aside from pest control. It's hard to pin down the nuances of cat culture, as any direct discussion with subjects about it is often met with lies or fabrication. What is known, however, is that all talking cats wear a collar and bell. They are gifted the collar and bell when they reach adulthood (~1 year). Where the collar and bell comes from and by who they are made remains a complete mystery, with young talking cats lacking them one day and appearing with them the next. It's theorized that the collar and bell is gifted to them by He of the Long Yarn. The collar and bell are similar in shape, but differ dramatically from one collar and bell to another. The bell is most often silent, even when jangled. But it's been confirmed that the bell rings with a note of truth whenever the cat doesn't tell a lie.
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Talking cats are still cats, however, despite their intellect. Lazy, proud, arrogant, full of personality. It's said that if you force a talking cat to tell the truth they will hold a grudge for life and search for ways to enact repeated revenge.
Talking cats live for a long time, with the oldest reported cat being well over 100 years old. It's said that their connection to lies is so strong that they view death as nothing more than another lie, which grants them their fabled 9 lives and long lifespan. While it's uncertain if it's true, a talking cat's lifespan seem affected by the number of times their bell rings over the course of their life.
Talking cats have their own language, which can be spoken using any other language, assuming they have a large enough vocabulary. Their language is one of contradiction, with lies substituting truth and metaphor substituting fact. Those that can twist their head around the language of talking cats will find them pleasant and easy to speak to.