Loreleï is rather young for a succubus. Old enough to be an adult, but still at an age she barely looked younger than that a human as old as herself. The same couldn't be said about her confident and personal doctor Azami Shingi, a nine-tailed kitsune so old and so powerful some say she qualifies as a goddess, but don't go say it anywhere near her. The imperial demoness wasn't sure what Azami saw in her to decide she needed to do everything she could to ensure Loreleï's good health, but she already revealed herself invaluable.
When Azami entered, she took care to stay unnoticed, instantly sensing there was something strange with the younger succubus. She had an idea of what, but needed more data before saying for sure she finally revealed her presence. This had for immediate effect to make the two succubus separate, making Louie's turn back to being a human boy.
After thoroughly examining the child in both form, she finally came to a conclusion. "You said Louie was possessed by a fog demon when he was forced into the cocoon?" Then, after briefly looking at Loreleï, she added "And I see you sacrificed your blood-stone so your husband would be their biological father. Being possessed by a demon, combined with the remaining traces of blood-stone magic in the second drop of blood… But with how easily it is for the ritual to go awry, surviving such conditions is a miracle. Wait, did you cry Lore?"
"Of course I cried! But what…?"
Before Loreleï could finish her question, the kitsune doctor explained "Tears of a pure, untainted soul can accomplish miracles. Just like when you were yourself in a similar cocoon, the tears of your then soon-to-be adoptive mother granted her wish for you to stay yourself even after your transformation, your own tears made sure Louie would live and be healthy."
The empress would have wanted to sate how she couldn't have purity of soul, but knew it was futile. By that point it was an old argument between Dr. Shingi and her.
Noticing her friend wouldn't voice her opinion this time, Azami took that opportunity to come back to the current problem. "Louie is in a quantum state. Saying that he is still unchanged and saying she turned into your biological daughter, on neither case would you would be lying. But because of how most living beings' brain work, we can only see one of those two states at a time. With the appropriate training, Louie should be able to control which of their two states is perceived at any time."
"Oh, and until she learn to properly feed as a succubus, keep your daughter away from her father and any friend she might have. Being a succubus yourself you're fine, but she might accidentally kill other species, especially humans."