Demon Twins

Zane and Zoe are demon twins with different abilities. Zane can read emotions and memories, appear in nightmares of those who hate him, can see people or places who aren't around her perfectly if Zoe is there and he wants to, project images into peoples minds, and use psychic electrokinesis. Zoe can create tentacles come out from her body, speak to animals telepathically, understand animals, cannot be affected by fire, and is strikingly beautiful. They used to live secluded in a house on an island that did have people- a tribe, to be precise -but no one dared to interact with them. A king named Spencer and his wife Queen Isabelle hear of this. The king orders some of his people to kidnap the twins. Zane was to marry a the only daughter , Princess Mary, and Zoe was to marry the middle son, Princess Malachi. (In the story, King Spencer's name has been changed to Henry, but I can't change it without messing something up, so warning.)