Person A and Person B are best friends. They are mutually crushing on each other. One day, Person A meets Person C and instantly falls in love. Person A never stops thinking or talking about Person C, absolutely smitten. Person B is suspicious of this, but Person A insists they're just jealous.
But it turns out Person C is a witch using a Siren Song spell to infatuate Person A completely, making them do whatever Person C says, in order to get to Person B.
