My Wolf is the Sun God

Apollo angered Zeus and was stripped of his power. What was left of him was a wolf, dying. He bit Hecate to stay alive, and the bite triggered an old fated bond contract that ties two lives and two pools of power into one shared supply. It made them master and servant, a fallen god and a broken goddess, neither of them willing. They went through the trials of Olympus tied together. He got strength back by drinking her blood. She healed on the solar essence coming off him. He changed as they went, from wolf, to a youth with wolf ears, to a man, and every step of it cost Hecate something she gave up on purpose. He built a pack of sun wolves for her and took them down into the underworld. Hades let loose Cronus, the primordial king of the gods, and in the middle of that Apollo worked out what his fall had actually been. Zeus and the Fates had arranged the whole thing, the loss of his power and his love for Hecate included, because the two of them together are the only thing standing between the world and Ragnarok.