Nakigitsune is a sword character from Touken Ranbu, a Japanese media franchise centred on historical swords personified as warriors, and he rarely speaks himself, instead letting his small fox companion voice his thoughts. Fans picked up the fox's repeated yaa yaa cry as a shorthand for the pair, sharing it in clips, edits and reaction posts across anime communities. Its short length and distinctive squeak make it easy to reuse, which is why it remains a recognisable in-joke for Touken Ranbu fans years after they first heard it.