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

Other days

camera

Camera Day
lumpy rug

Lumpy Rug Day
kale

Kale Day
first love

First Love Day
lisp

Lisp Day
gum

Gum Day
ruby

Ruby Day
polyamory

Polyamory Day
eat what you want

Eat What You Want Day
prosecco

Prosecco Day