Sure.
The Djinn in Ghoul Goblin was "assigned" to a guide - a man in Egypt as his guardian. A young woman hired the guide to take her into a tomb. The tomb collapsed and the djinn, in love with the young woman, saved her instead of his charge. The woman and the djinn fled together to the United States. Years later, the djinn sacrificed himself to protect the last remaining members of a cursed, mortal family. I believe he merged with Harry briefly to do so.