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

Other days

china

China Day
hoodie

Hoodie Day
lumpy rug

Lumpy Rug Day
ride the wind

Ride The Wind Day
lash

Lash Day
brow

Brow Day
comfy

Comfy Day
fiancee

Fiancee Day
my little pony

My Little Pony Day
bubble bath

Bubble Bath Day