Milk, also called Chao, is a character that appears in the Sonic the Hedgehog series. They are a Chao who ended up in Dr. Eggman's Incredible Interstellar Amusement Park and got entangled in the affairs there.
Ending up in Dr. Eggman's Incredible Interstellar Amusement Park, Milk would be chased by Orbot and Cubot, who mistook them for a Wisp. However, they were saved by Sonic and was in deep gratitude to the hedgehog. Later, Milk met Cream and Cheese, where they were being chased by Cubot again. After Sonic saved them, Cream noticed their new Chao friend did not have a name. Tails suggested they called him "Tornado," but when the Chao did not like the name, Cream suggested calling them "Milk," a name the Chao approved of.
- Though Milk is genderless, they were referred to as male in Sonic Colors.
- Milk's name may be a reference to how Cream and her family members (Vanilla, Cheese and Chocola) are all named after food products. In addition, Milk's name is derived from a dairy product, just like Cream and Cheese's.