Oops, it doesn't look like 'take a woman who is not your wife to lunch day' is a national day..

Other days

Ask Out Your Crush Day

Appreciate Yaself A Lil Extra Day

Hoodie Day

Martini Day

African Immigrant And Refugee Hiv And Hep Awareness Day

Girl Friend Day

Tell A Fairytale Day

Polyamory Day

Ride The Wind Day

Stud Day