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

Other days

kiss a ginger

Kiss A Ginger Day
ormille

Ormille Day
gum

Gum Day
cat girl

Cat Girl Day
nae nae

Nae Nae Day
carpenters

Carpenters Day
boy friend

Boy Friend Day
camera

Camera Day
ask out your crush

Ask Out Your Crush Day
bounce

Bounce Day