A bit of spoilery picture, but I had to make it. One of my favorite relationships in my story is between the de-throned god Monstra and Raana.
Monstra had power over other snake's will with his magical eyes. But a rebellion was led against him and his family was masacred. A young snake Sethek managed to cut out Monstra's eyes during the battle, but couldn't kill him, so they crafted a prison for him.
Centuries later Monstra's prison is worshiped by his secret followers in the jungle, who can't break the seal keeping him imprisoned. They hold sacrifices for him in hope they can break the seal that way, but it never works and Monstra only grows disgusted at them. Until one day a little girl is about to be sacrificed and Monstra senses the power of one of his daughters in her. He sends visions to the little girl to wish his freedom and thanks to his daughter's power, the seal breaks. Monstra kills all of his worshipers but keeps little Raana safe. The little girl who just lost her parents and her life, quickly accepts him as a father-figure and becomes his most loyal priestess. Monstra often calls her "daughter" but only because of his true daughter's magic is inside her. Raana later in her adult life understands this, but chooses to ignore it.
I just... love that he grows in my head, from the generic evil god of the tale into something more complex. He is very confused, not being able to adjust his mind to the passing of time. He is furious about it and tries to keep himself to his main goal. But he still slips with names and events and it frustrates him. The only person he can trust is Raana, who sees these failings, but forgives him, because still sees him as a father. This also motivates Raana, because she believes her "father" will be better if he achieves his goal.