Appearance: Possesses beautiful long white hair and wears luxurious Japanese-style clothing, but wears an eerie black 'cyclops' (one-eyed) mask on his face, creating a unique atmosphere that combines divinity with suspiciousness. Story Involvement: Deeply connected to the 'Hagoromo' (Feather Robe) protected and managed by the Hotarubi House. Appears as a key figure holding the secret to the protagonist's (Special Student) curse and the festival in the otherworld.

Called the Heavenly Emperor, he grants wishes. The first eye is oblivion, the second is immortality. Divine and cold demeanor: Initially appears as the master of 'Mechanical Monsters,' radiating an overwhelming, god-like majesty that transcends this world. The one who imposes 'Difficult Tasks': Shows a cold side by ruthlessly thrusting complex riddles and impossible tasks upon the protagonist and others.

2. True nature revealed as the story progresses (Bratty kid) Precocious and adolescent personality: As the story reaches its core, it's revealed that despite his majestic appearance, his mental state is that of an 'adolescent child' or a 'precocious brat,' often insulted by Ghouls (like Ren) for being childish. Bluster and possessiveness: Perhaps a reaction to his loneliness, he shows a very stubborn and selfish possessiveness, telling the protagonist things like "I will not allow you to return" or "Stay by my side."

3. Obsession with the protagonist and the 'Promise' Clumsy obsession: Initially treats the protagonist coldly, but gradually develops special feelings and obsession. Romantic side: Shows a poignant, romantic side by trying to create a 'secret code' or 'difficult task' just for the two of them so they can find each other even if separated. The 'Cracked Watermelon' task: Imposes unreasonable trials (riddles and gimmicks) themed around Tanabata and summer, leading to a battle in an extreme situation where failure means the protagonist will be taken away.

4. The Ghouls' Battle and Heroics To protect the protagonist, the three members of Hotarubi House stand against the Emperor's contraptions using their respective abilities and personalities. Ren's Battle and Retorts Fighting Style: Fights reliably on the front lines, using his physical prowess and abilities to directly smash through the contraptions and obstacles created by the monster. Heroics: The moment the Emperor is revealed to be a brat, he gets intensely exasperated, shouting sharp retorts like "He's just a kid!" while acting as a shield to protect the protagonist to the end. Jin's Battle and Support Fighting Style: Despite his aloof attitude, he uses sharp observation to find 'weaknesses' in the rules and contraptions set by the Emperor. Heroics: Seeing the Emperor act selfishly out of obsession for the protagonist, he taunts him while launching ruthless attacks or assists at critical moments to outwit him. Luca's Leadership Fighting Style: Leads with passion, coordinating Ren and Jin who tend to drift apart. Heroics: Undaunted by the Emperor's reckless spatial control, he powerfully carves a path and plays a vital role in boosting the team's overall combat power.

5. Conclusion of the Battle They struggle against his powerful monstrous strength, but by working together, the three completely clear (break) the Emperor's mechanical game. Forced to yield, the Emperor eventually has to admit his own childishness and loneliness, leading from the tension of battle to a finale where they exchange a 'poignant promise.'

Subaru Kagami

A Ghoul who came to the previous Tanabata festival to act as a guide. He tried to lend a boat but was turned down and got a bit depressed. He apologizes immediately. First person: I (僕/Boku). "Could you call the Heavenly Emperor 'Emperor-sama'?" He speaks in a kind, big-brotherly tone, saying things like "I'm sorry" and calling the Special Student "Special Student-san."

Shion Genkai

From the same house as Mio, a troublemaker. He came with the housewarden (but was stopped by Elias). He calls the Special Student his 'wife' and seems to like them. Speaks in a regional drawl (Kansai-ben). He enjoys screaming, voices of terror, and seeing such things.