An old castle in Eastern Europe that’s been renovated into a hotel…
Traveling all the way from Japan, the protagonist proposes to his girlfriend there, and she accepts.

However, an unexpected phone call causes his girlfriend, now-fiancée, to take an emergency flight back home for work reasons.

Once left on his own, the protagonist has a strange dream.
He becomes a woman, invited into an era when the castle still flourished.
When he wakes from his dream, he realizes with shock that he’s physically transforming into the woman he was in his dream.

And although he struggles to find a way to change back, every time he sleeps, he’s taken to the dream world―the castle during the Middle Ages. Every time he wakes from the dreams, his body comes closer to becoming that of an actual woman.

His girlfriend accepted his proposal, but he can’t get back to her like this.

Will he escape his dreams? Can he transform back into a man?
Or will the future take a turn in an unseen direction…?