The werewolf king and his wife

On a rainy night, the new wolf king gets seriously wounded when he was fighting with his enemy. After getting wounded, his power vanishes, and he becomes a little wolf. One girl saved him and came back with him to her house. Then she nurses and heal him. From then on, the little wolf stays with her. When he gets back his all power one day, suddenly the wolf leaves without saying anything to her. But later when he came back to her house to take her, he didn't find her anywhere.