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

Other days

camera

Camera Day
bounce

Bounce Day
stud

Stud Day
polyamory

Polyamory Day
kale

Kale Day
artists

Artists Day
cat girl

Cat Girl Day
my little pony

My Little Pony Day
ride the wind

Ride The Wind Day
tulip

Tulip Day