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

Other days

book

Book Day
cursing

Cursing Day
youth

Youth Day
pumpkin

Pumpkin Day
stress awareness

Stress Awareness Day
frozen yogurt

Frozen Yogurt Day
carpenters

Carpenters Day
hiv awareness

Hiv Awareness Day
first love

First Love Day
kale

Kale Day