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

Other days

azonto is acceptable

Azonto Is Acceptable Day
tell a fairytale

Tell A Fairytale Day
girl friend

Girl Friend Day
self appreciation

Self Appreciation Day
promposal

Promposal Day
boy friend

Boy Friend Day
ormille

Ormille Day
chocolate milkshake

Chocolate Milkshake Day
first love

First Love Day
believe

Believe Day