So. . .I've done a St. Bosco seance. Who exactly was St. Valentine. And what effects might you all imagine using his story?

Mark

Mark,
There were several St. Valentines. The one associated with the day was martyred in Rome during the 3rd century under Claudius II.
His actual execution took place on Feb 15 but that, apparently was close enough for the early church leaders, who wanted some event to counter the pagan festival at that time, Lupercanalia.
For effects, depending on stage or close-up, you might try Needle Thru Heart-shaped Balloon, for stage, or my Cards for Lovers, for close-up.