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

Other days

artists

Artists Day
tulip

Tulip Day
frozen yogurt

Frozen Yogurt Day
emoji

Emoji Day
boy friend

Boy Friend Day
bow tie

Bow Tie Day
promposal

Promposal Day
self care

Self Care Day
unicorn

Unicorn Day
pumpkin

Pumpkin Day