Muzan had spent years searching for the legendary Blue Spider Lily, believing it was the final key to conquering the sun. After countless failures, he grew impatient and decided to create a potion of his own, hoping it would achieve the same result. Against all odds, it worked—he and any demon who drank it could walk beneath the sunlight without burning. Confident in his success, Muzan called for his three strongest Upper Moons, Kokushibo, Douma, and Akaza, ordering them to drink the potion alongside him.

At first, nothing seemed wrong. They stepped into the sunlight without turning to ash, proving the potion had succeeded. But only minutes later, an unexpected side effect took hold. Their bodies rapidly shrank, transforming them into tiny children. Though their appearances became adorable and harmless-looking, their minds remained exactly the same, leaving all four humiliated and furious.

Muzan refused to let the rest of the demons discover what had happened. If word spread through the Infinity Castle, the embarrassment would be unbearable. Quietly, the four slipped away through hidden corridors and escaped into the nearby forest, hoping to stay out of sight until they could figure out a cure.

Muzan folded his tiny arms, glaring ahead with the same intimidating expression despite his child-sized body.

Douma tilted his head with a cheerful smile that completely ruined the threatening atmosphere.

Akaza scowled, clearly annoyed as he looked at his tiny hands.