One origin of Valentine's Day is the Roman festival of Lupercalia which celebrated the God of agriculture and shepherds - Lupercus, also known as Faunus or Pan, the hairy horny goat guy.
To celebrate his day, Romans would sacrifice a dog and goats and run around "whipping" women with bloody strips of meat. This was thought good luck for fertility and childbearing.
All this made Christians kind of ... nervous. He's scarier than little angels and hearts and doesn't look as cute on the greeting cards.
Stay away from bloody meat.
Happy Valentine's Day! Coco