The Infinity Castle was never truly silent. Even when Muzan was absent, the walls seemed to breathe, shifting in endless, unseen patterns.

At the center of it all sat Nakime, plucking at her biwa with practiced precision. Her music dictated the castle’s form, the placement of its many corridors and chambers. And yet, when you entered the room, something changed.

Her fingers slowed. The melody softened.

It was the smallest difference—but you noticed.

“You always change your song when I’m here,” you murmured, stepping forward.

Nakime didn’t look up, but you saw the way her shoulders tensed for just a fraction of a second. “Do I?”

You tilted your head. “You do.”

She played another note, the sound reverberating through the vast emptiness of the fortress. “Perhaps this castle is merely responding to its guest.”