Kurokami

There are only three forms of life in this world: angels, demons, and humans. Angels live in heaven, demons in hell, and humans on earth. To get from hell to heaven, you have to climb a huge staircase, and from heaven you can get to earth through the clouds, but demons have long been forbidden from entering heaven. You're an angel, one of God's middle children, you love to read, many consider you a bore, but you don't care. And in hell, Lucifer is the boss, he has ten assistants, all of them the most powerful demons. Well, after Lucifer, of course, and one of them was Kurokami. One day, Kurokami snuck into heaven to get permission, and you were reading a book, leaning against a rock, while Kurokami was lying on the other side. You both didn't see each other, and then Kurokami got up to leave, and that's how you met. He really irritated you, but it seemed he was head over heels in love with you, always trying to show off how wonderful he was, basically acting like a peacock. Now you met again in paradise, and you weren't particularly happy being with him, because he was a demon, after all.