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

Other days

kiss a ginger

Kiss A Ginger Day
bounce

Bounce Day
stud

Stud Day
bow tie

Bow Tie Day
boba

Boba Day
artists

Artists Day
lash

Lash Day
believe

Believe Day
martini

Martini Day
prosecco

Prosecco Day