Oops, it doesn't look like 'biffl day' is a national day..

Other days

boy friend

Boy Friend Day
unicorn

Unicorn Day
ponytail

Ponytail Day
tell a fairytale

Tell A Fairytale Day
fiancee

Fiancee Day
carpenters

Carpenters Day
cuddle up

Cuddle Up Day
bonang

Bonang Day
reading

Reading Day
youth

Youth Day