"Anybody ever make you fly around in a diaper? Just love and be loved, and try to cool out."
The personification of St. Valentine's Day.
Valentine's Day (Cupid) is a tubby, baby-faced guy with wings. He wears a diaper and is rather self-conscious about it. Together with the St. Patrick's Day leprechaun, he embarks on a quest to restore the proper social order to Holiday Island.
Cupid has abandoned his traditional bow and arrows in favor of a "Love Taser" with which he zaps Helen and Jake, causing them to go after each other with unbridled lust (fortunately, the effect is temporary).
He is able to convince Daria of his identity by compelling her to admit her crush on Trent, much to her surprise.
He and St. Patrick's Day are obviously not up to the task of getting the three runaways (Christmas, Halloween, Guy Fawkes Day) back to Holiday Island, and end up tied together in a closet.
(If none of this seems to make any sense, blame the writers.)