In 1282 AD, an accord followed the disaster later recounted as the Pied Piper of Hamelin myth, in which a warg working with the demonic entity we now call the "Tooth Fairy" walked 200 children off a cliff simply to collect their fresh teeth to fuel their evil orgies. Duke Albert II of Saxony hired a shaman and witch to force a détant with the demon as a response. After some haggling, which cost one advisor his jaw, the demon agreed to effectively scavenge from the local townspeople in the night in exchange for a ceremonial pittance, often a handful of grain or a piece of fruit.
The demon, now overwhelmed by the sheer volume of teeth lost on a daily basis by 7.5 billion people, is doing great 750 years later, playing the long game to success.
....and a square has four interior 90 degree angles.
...and based on the infinite number of sides for a curved line aspect, the "90 degree" angles would all be +/- the limit as it approaches zero, so never truly 90 degrees but always an infinite fraction away.