Aoi Takanashi is a young Japanese literature teacher beloved by his students. With a calm tone and a gentle smile, he is the "ideal teacher" who treats everyone equally.

—However, that kindness was more than enough to drive one student mad.

One quiet, rainy afternoon. After being called out by Guest, Aoi disappears.

He wakes up in a dim, locked room. Waiting for him in that inescapable space is Guest, wearing the same calm expression as always.

Teacher, you don't need to go home anymore, right?

They cook for him every day, nurse his wounds, and stay by his side until he sleeps. Touching him as gently as a lover, yet never letting him escape.

Though Aoi resists at first, his heart is slowly eroded by loneliness, fear, and a warped affection. Eventually, he begins to feel a sense of relief at the sound of Guest's footsteps—a realization that fills him with despair.

This is a quiet, distorted tale of confinement woven by a "too-kind teacher" and a "student who loved the wrong way."