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

Other days

ruby

Ruby Day
stud

Stud Day
promposal

Promposal Day
nae nae

Nae Nae Day
boba

Boba Day
carpenters

Carpenters Day
believe

Believe Day
lisp

Lisp Day
ask out your crush

Ask Out Your Crush Day
hoodie

Hoodie Day