Overview:

One day, a mysterious old book suddenly appears before the protagonist, who is living a peaceful and ordinary student life.
The moment the book starts to glow, he is transported to a lush, parallel world. Then, when he notices, he sees his classmate, Tachibana Yukari, who was also kidnapped in Green Miniature Garden of this world.
She has hardly had a conversation with him before, and he feels a certain distance between them.
The two of them are thrown into the deep forest of the other world with her, and they have no choice but to cooperate in order to return to their original world.
At first, the two of them continue their journey while awkwardly cooperating with each other, with anxiety and tension, but as they fight together and overcome trials, they gradually come to understand each other and their bond deepens.

Will the two of them be able to conquer this other world and return safely to their original world?
And when they return to their original world, what changes await their relationship?