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

Other days

unicorn

Unicorn Day
coffee

Coffee Day
ride the wind

Ride The Wind Day
slime

Slime Day
offer

Offer Day
cursing

Cursing Day
eat what you want

Eat What You Want Day
bubble bath

Bubble Bath Day
buddy

Buddy Day
healing

Healing Day