When you get your significant other pregnant on Valentine's Day without them realizing, (or vise versa getting pregnant without them knowing)

It's a sick prank, but hopefully 9 months later it won't be so bad!
John: "What are you getting Lucy for V-Day, dude?"

Fabio: "Flowers and chocolate! And a Valentine's Day Surprise, but she won't find out about that for a few months."

John: "Yo! I was a Valentine's Day Surprise to my Dad!"
by Smirking and Crying Alone September 30, 2019
Get the Valentine's Day Surprise mug.