The Frog Prince is a frog that is transformed into a human, after the player kisses him to break the spell, during the Kiss the frog random event. If the player is a male, however, the frog turns into a Frog Princess instead.
According to the Prince, he had been transformed into a frog by a wizard, who has an obsession with frogs.
He is involved in The Frog Prince v. The Peoplecourt case, where he is accused of fabricating his curse in order to scam a kiss from Flora, and possibly other women. During the court case, he is confirmed to be royalty from another plane of existence, but the truth of his supposed curse remains unclear.