Alcestis

Apollo was, at one point, banned from Olympus for nine years. During this time he served as a shepherd for King Admetus of Pherae[?] in Thessaly. Since Admetus treated Apollo well, the god promised him that when it came time for King Admetus to die, another would be allowed to take his place. Admetus then fell in love with Alcestis. Her father, though, King Pelias would only give permission if Admetus rode a chariot pulled by lions and boars and other wild animals. Apollo helped Admetus accomplish this and the pair wed. When it did indeed come time for Admetus to die, Alcestis agreed to die for him. Heracles intervened and both of the pair were allowed to live.