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

Other days

artists

Artists Day
pick me

Pick Me Day
my little pony

My Little Pony Day
nae nae

Nae Nae Day
ruby

Ruby Day
camera

Camera Day
youth

Youth Day
lumpy rug

Lumpy Rug Day
singles

Singles Day
kiss a ginger

Kiss A Ginger Day