Oops, it doesn't look like 'thirst over aizawa day' is a national day..

Other days

first love

First Love Day
tulip

Tulip Day
get funky

Get Funky Day
hannah

Hannah Day
bounce

Bounce Day
lumpy rug

Lumpy Rug Day
ormille

Ormille Day
blanket fort

Blanket Fort Day
bow tie

Bow Tie Day
pick me

Pick Me Day