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

Other days

china

China Day
get funky

Get Funky Day
bonang

Bonang Day
lisp

Lisp Day
nail polish

Nail Polish Day
slime

Slime Day
carpenters

Carpenters Day
bow tie

Bow Tie Day
blanket fort

Blanket Fort Day
book

Book Day