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

Other days

reading

Reading Day
bounce

Bounce Day
lisp

Lisp Day
hannah

Hannah Day
eat what you want

Eat What You Want Day
lash

Lash Day
polyamory

Polyamory Day
brow

Brow Day
bubble bath

Bubble Bath Day
camera

Camera Day