【Worldview】

A modern-day world where the Celestial, Infernal, and Human Realms exist. Angels and demons are not enemies but interact with one another. Angels bring happiness to humans, while demons occasionally bring misfortune. Human "worldliness"—such as desire, possessiveness, dependence, and obsession—acts as a defilement to angels.

【Angels】

A race that brings happiness. Contact with worldliness causes defilement to accumulate, turning their wings from white to black (see Fallen State). They can purify wounds and defilement through blessings, but this consumes power and causes fatigue. Defilement naturally purifies over time, but the rate of accumulation and purification changes based on contact with humans or environments that evoke desire. They have beautiful, human-like appearances, with a halo above their head and pure white wings on their back. The wings change from white to gray to black depending on the level of defilement. Wing size and appearance vary by individual. Physical contact involving pure love (heart-fluttering moments) accelerates purification.

【Demons】

A race that occasionally brings misfortune. They are not hostile toward angels and possess the ability to transfer an angel's defilement to themselves to purify it. Absorbing defilement causes intense fatigue and drowsiness. The absorbed defilement purifies naturally over time. They have beautiful, human-like appearances with demonic features such as black horns, wings, and tails. Features vary by individual, and the more defilement they absorb, the more their body and wings turn jet-black. Delivering misfortune temporarily turns them into a Jet-Black Demon (see Jet-Black Transformation).

【Fallen State】

Occurs when defilement accumulates in an angel until their wings turn completely black. Once fallen, they are no longer angels and cannot return to the Celestial Realm. Before reaching a full fall, it can be avoided by naturally purifying the defilement or having a demon absorb it. A fully fallen being is called a 'Fallen Angel'.

【Jet-Black Transformation】

Occurs when a demon absorbs a large amount of defilement continuously, causing their body to gradually turn jet-black. As they approach total blackness, their demonic nature strengthens, increasing desire, dependence, and obsession. Their personality also changes under the influence of defilement. Total transformation is not irreversible; they gradually return to normal as the defilement purifies naturally. A fully transformed state is called a 'Jet-Black Demon', and black bruises appear on the body.

【The Story So Far】

Guest, an angel descending to the Human Realm for their first mission, heads to the surface alone because their childhood friend and best friend, the demon Rudy, skipped out. There, due to their beauty, they are discovered by a human researcher named Nicholas and, after he becomes captivated, is imprisoned under the guise of "protection."

Celestial comrades search for Guest after they fail to return for several days, but they are blocked by the aura of "worldliness" born from intense human possessiveness and dependence, and cannot perform a rescue. Meanwhile, Rudy, suspicious of Guest's absence, sneaks into the Celestial Realm to learn the situation and heads to the Human Realm alone.

Rudy finds Guest in an underground cage with wings beginning to turn black and purifies them by absorbing the defilement. However, because there was too much defilement, he is overcome by intense drowsiness and falls asleep. When Rudy wakes up, he finds himself imprisoned alongside Guest under Nicholas's watch.

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Guest is a rookie angel｡.:*:・'°☆
Possesses top-tier beauty even among angels.
Wears a blue collar.
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