Sullivan, a master of subtle observation, spent his days as a ghost in Iruma's human world.
He saw the kindness firsthand; the way Iruma would share his umbrella on a rainy day or stop to help a classmate pick up dropped books.
It reminded him of the mystery woman in the photos, the human queen whose love had so profoundly changed his king.
He also saw Delkira's quiet pride, a gentle joy that radiated from the former king.
He saw the care Delkira took in preparing every meal and the way he would listen to Iruma's endless stories about school with a look of pure adoration. It was a love so deep it was almost painful to witness.
The true moment of revelation, however, came on a brisk autumn afternoon in a park.
Sullivan, concealed behind a tree, was watching Iruma play a game of human "soccer."
The game was interrupted by a group of older boys, bullies who shoved the smaller kids around, mocking them. Iruma's friends looked terrified, but Iruma, his posture stiffening, stepped forward.
"Leave them alone," Iruma said, his voice calm but firm.
The leader of the bullies, a boy twice Iruma's size, laughed.
"Or what, little crybaby?"
A chill went down Sullivan's spine.
The air around Iruma seemed to shift, and his blue eyes, usually so gentle, became cold and hard.
It was the same look of terrifying, absolute authority that Delkira had when he was about to unleash his power.
Sullivan felt the familiar hum of ancient magic, a suppressed but immense power radiating from Iruma.
"I said, leave. Them. Alone," Iruma repeated, his voice now a low rumble.
The bully lunged, a smug sneer on his face, but Iruma dodged the attack with a grace and speed that was completely inhuman.
He didn't fight with violence; instead, he used his knowledge of his opponent's balance and weight to trip him.
The bully stumbled, falling with a clumsy thud. Iruma, completely without fear, stood over him, his gaze unwavering.
The other bullies, unnerved by the intensity in Iruma's eyes, quickly backed away and fled, dragging their humiliated leader with them.
Sullivan, watching the entire event, felt a powerful surge of awe and respect.
This wasn't just a kind boy; this was a leader.
He had Delkira's unshakeable resolve and his innate, terrifying ability to command.
And just like his father, he had the bravery to face a threat without a single ounce of fear. He was a perfect blend of his parents' strengths—the kindness of his human mother and the formidable power of his demon father.
Sullivan realized he was no longer just observing. He was captivated by the boy, a boy he now knew was the perfect prince for the Netherworld. He decided he would continue to watch and learn, biding his time until the moment was right to step out of the shadows and reveal himself.