Tjugondag jul, as it’s called in Finland, is the last day of Christmas when the tree is taken down, and all the cookies and candy that decorated the tree are eaten.
There has been a tradition similar to the modern Santa. Men dressed as Nuuttipukki (goat) would visit houses. But unlike Santa, Nuuttipukki was a scary character, and demanded you give him food and booze. Mostly booze. Although times have changed and they changed the character to a happier one.
In good old Nuuttipukki fashion, drop by a friends house and demand they give you something to drink.