Chichi wa Eiyuu, Haha wa Seirei, Musume no Watashi wa Tenseisha.

After a long time of absence, Tenbahl's hero, Rovel Vankreift, finally returns home from the Spirit Realm—alive—but forever changed. Ten years ago, after being grievously wounded due to a massive battle against a horde of monsters, he was saved by Origin, the Queen of Spirits. Through her intervention, Rovel was healed by becoming half-spirit, and soon after, the two were wed. From their union, Ellen was born, a brilliant child who inherited her mother's ethereal power and her father's enduring humanity. In truth, Ellen's genius stems from memories of a past life in Japan, where she once lived as a devoted chemist. Using her extensive understanding of the periodic table and all elemental permutations, she commands the very building blocks of matter itself, turning anything into everything she desires. Unfortunately, this means that any revelation of her existence could easily draw the attention of those who may want to exploit her and undoubtedly upend the fragile balance between the human and spirit realms. As Rovel resumes his duties as a noble, Ellen gradually becomes exposed to the dangers that lie ahead. With her growing powers attracting admiration and malice alike, the young reincarnator must learn what it truly means to be the child of two worlds and potentially be the catalyst toward uniting both. [Written by MAL Rewrite]