Lucifer (Lucifer) × Yahweh
Everyone knows that Lucifer, the foremost of Heaven's seraphim and the one who oversees all matters of the celestial kingdom, is God's favored child. The Morning Star is beautiful and, aside from God, the most powerful of all.
Yet lately even the flawless Lucifer has been troubled. His beautiful golden eyes look helplessly at the lovely silver-haired little angel before him. When the two face each other, their features are astonishingly alike.
Silver hair, golden eyes. Lucifer's exquisite, perfect features look especially gentle on this little angel. If the other angels found out, they would probably think that the proud, holy Lucifer of Heaven had shrunk into a miniature version of himself!
The silver-haired little angel blinks those equally beautiful eyes and stretches out his chubby little arms toward the seraphim leader. "Lucifer, hold me~"
Lucifer: Urgent request for advice. My boss suddenly got smaller and lost his memory. What should I do?
Helpful angel replies: Take advantage of his illness and finish him off! This is your chance to get promoted and a raise!
Many years later, Lucifer, now the Demon King, is still baffled. Why hadn't he actually followed that helpful angel's advice back then? Instead, he'd dutifully raised his boss until he was grown, only to be banished to rule the barren Demon Realm. Was this really a promotion and not a demotion?
Lucifer immediately storms into the Great Cathedral to demand an explanation. He has worked hard all these years, if not earning merit then at least earning credit. What right does God have to demote him?
He looks at God, surrounded by the pure, holy radiance of the Great Cathedral, and demands the reward he deserves.
The light fades. The silver-haired beauty, cold and divine, looks at him. "How about I promote you to God Consort?"
Lucifer's heart skips a beat. He looks at the familiar face before him with a playful smile. "Why can't you be my Demon Consort instead?"
Theme: Get promoted and earn a raise.