Songfacts®:

• In this love song vocalist Ville Valo continuously refers to St. Valentine, after whom Valentine's Day is named. There are varying opinions as to the origin of Valentine's Day. Some experts state that it harkens bark to the third century Roman Empire and specifically the rule of Emperor Claudius II (268-270 AD) who decided to abolish the institution of marriage, as he felt husbands did not make good soldiers. He attempted to enforce the new law with the utmost rigor, however in Rome Bishop Valentine considered such a policy against the spirit of God and of human nature. The bishop's "crime" was discovered and on February 14, 269 AD Saint Valentine was arrested, imprisoned, and brutally clubbed to death. Gradually, February 14th became the date for lovers to exchange hand-written messages of affection, and St. Valentine became the patron saint of lovers.
  The Duke of Orleans sent the first valentine card to his wife while he was imprisoned in the Tower of London in 1415.