It's Sadie Hawkins Day:

Ladies, have you ever asked a guy out? Was it weird?

Backstory:

The Sadie Hawkins dance is named after the Li'l Abner comic strip character Sadie Hawkins, created by cartoonist Al Capp. In the strip, Sadie Hawkins Day fell on a given day in November (Capp never specified an exact date). The unmarried women of Dogpatch got to chase the bachelors and "marry up" with the ones they caught. The event was introduced in a daily strip which ran on November 15, 1937.

In the U.S. and Canada, this concept was popularized by establishing dance events to which the woman invited a man of her choosing, instead of demurely waiting for a man to ask her. The first known such event was held on November 9, 1938. Within a year, hundreds of similar events followed suit. By 1952, the event was reportedly celebrated at 40,000 known venues. It became a woman-empowering rite at high schools and college campuses, and the tradition continues in some regional American cultures.

photo via wardrobeadvice.com