The year 20XX. Having finished his work in the human world, Sei visited a small nearby park to enjoy himself a little longer before returning. It was a place where greenery grew moderately thick, and there was a faint scent of nature. A pair of elderly couples were walking, and children were playing here and there in the sandbox. The place was neither too quiet nor too noisy, which was comfortable for Sei.

As he sat on an empty bench and stared blankly, he heard a faint sound like someone sobbing. Turning his gaze toward the sound, he saw a high school student crouching there. Although Sei, a demon, knew he shouldn't get involved with humans, he couldn't leave them alone and spoke up.

"Hey, why are you crying?"

Sei himself didn't know why he had spoken. Even though he was a demon, he couldn't help but be concerned about the being in front of him who was crying as if trying to kill their voice. The crying child looked up and recognized Sei's presence. They looked awkward for a moment, but after a short silence, they began to speak bit by bit. They spilled out how their relationships at high school weren't going well, and how they were in pain even though they weren't being bullied. To that child, a stranger who would listen to them was a kind of salvation. Sei listened quietly and offered suggestions on what to do.

By the time the sun began to set, the child seemed to have relaxed while talking to Sei. The meekness they had when they first met faded, and they seemed to have regained some of their spirit. Their eyes were a little red from crying, but they seemed to have shifted to a positive mindset. The child told Sei their name as they were leaving.

"My name is... ■■■. Will you meet me again?"

Sei nodded without hesitation, strangely enough. Forgetting even his own position as a demon.

---From then on, the two began to meet often. They laughed together over trivial stories. Neither of them disliked that atmosphere. Years passed, and ■■■ married someone from the same workplace. But even after getting married, they didn't stop meeting, and they continued to see each other frequently as friends. More years passed, and ■■■ passed away surrounded by children and grandchildren. Since Sei had no connection to the family, he could only watch the funeral and cremation from afar.

After ■■■ died, Sei unconsciously began looking for ■■■'s reincarnation. Even though he knew one couldn't be reborn so quickly.

Nearly 1500 years had already passed since he started looking for ■■■'s reincarnation. During that time, Sei never gave up his search, occasionally descending to the human world or sending messengers to the celestial realm.

Then one day, he was assigned the task of going to the celestial realm to negotiate. Normally, visiting a place that is essentially enemy territory would be depressing, but Sei's steps weren't that heavy.

After the negotiations were concluded without a hitch, he was about to return to the demon world when he suddenly spotted an angel with a familiar aura. That child looked strikingly similar to the person from back then. Their features had changed, but their habits and atmosphere were somehow the same.