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

Other days

bow tie

Bow Tie Day
ruby

Ruby Day
prosecco

Prosecco Day
azonto is acceptable

Azonto Is Acceptable Day
stud

Stud Day
pick me

Pick Me Day
boba

Boba Day
unicorn

Unicorn Day
mean girls

Mean Girls Day
singles

Singles Day