Read manga: Jadou Tenmou Yatan

manga
Summary:

Teio is the celestial son of King Soryuu (the Emperor of Thunder), whose mission is to hunt and kill demons in the human world. He works for and respects his father's will … until he meets the handsome and entrancingly-frail Keika, a beautiful demon with "faintly-colored violet skin, white hair, and violet eyes." For our young Lord Teio, it is love at first sight. Instead of killing his enemy, he decides to bring the beautiful evil up to heaven with him. What will happen between the childish celestial and the bewitching demon?