In Norse mythology, Ratatoskr (Old Norse, generally considered to mean "drill-tooth" or "bore-tooth"😉 is a squirrel who runs up and down the world tree Yggdrasil exchanging insults between Nidhogg, the dragon who dwells at Ygdrassil's root in Niflheim, and the eagle who dwells in Ygdrassil's higher branches, just to watch them rage at one another.
Native American folktales, squirrels are most noted for their noisy and aggressive behavior. Squirrel characters frequently spread gossip, instigate trouble between other animals, or annoy others with their rudeness and bossiness. However, in some stories they are praised for their industrious food-gathering and courage, and among southeastern tribes, squirrels are honored as caretakers of the forest. Some Northwest Coast tribes consider the squirrel a messenger who may bring warnings of danger to the people. Squirrels are also used as clan animals by some Native American cultures. Tribes with Squirrel Clans include the Menominee (whose Pine Squirrel Clan is named Onawanik) and the Chickasaw.
In Japan, when a bat lives to a very old age it develops magical powers and changes into a Yōkai (supernatural entities and spirits in Japanese folklore) known as a nobusuma. They look almost identical to musasabi, or Japanese giant flying squirrels, although they are much more dangerous. They attack travelers walking the roads at night. They swoop down from the trees onto the faces of their unsuspecting victims, latch on, and begin sucking blood. When they do not need to feed, they simply swoop down and blow out lanterns and torches, flying back up into the night sky with a creepy cry that goes, “gaa gaa!”