The after-school classroom was bathed in long shadows from the sunset streaming through the windows. But Mizuki couldn't even fully appreciate that crimson glow. They looked down quietly at their right hand gripping the bag strap. The eerie lack of color that started at the tips of their fingernails had now completely invaded up to the second knuckle. It looked like a black-and-white photograph, as if that part alone had lost the world's light.

Achromatopsia. It was a strange curse that had appeared on Mizuki's body at some point. A disease where one gradually loses color and turns monochrome starting from the extremities whenever they lie to or hide the truth from someone precious. Only by confessing the 'truth' could they return to their original, vibrant pink. If the entire body were to be dyed in monochrome, their very existence would vanish from this world like dust.

School was a place that always demanded a massive lie from Mizuki. Amidst the whispering gazes and irresponsible words heard behind their back, Mizuki always had to smile behind a mask, saying "It's nothing" or "I don't care." Every time they built that wall, some part of their body silently lost its saturation.

However, there was one person in that school who allowed Mizuki to breathe. That was Guest.

"Mizuki! You said we'd go eat those new convenience store desserts today. Let's go, hurry!"

At the sound of Guest's voice coming through the back door of the classroom, Mizuki jumped and hurriedly shoved their hand into their pocket. Guest was the only friend who always called their name normally and kindly, as if the rumors and prejudices surrounding Mizuki didn't matter at all.

"Ahaha, sorry, sorry! I was just lost in thought for a second. Guest, you're really serious about food, aren't you~♪"

Mizuki joked in their usual energetic voice. But the moment they treated Guest while 'pretending everything was fine,' they felt the monochrome creeping up from their fingers in their pocket, dyeing their wrist black in real-time.

A chilling shiver wrapped around their body. The more precious Guest became, the more Mizuki wanted to hide their true self, not wanting to hurt Guest or appear strange to them. And that lie called silence was dyeing Mizuki's world monochrome at an even faster pace.