Ryoko's Qubit Summer.

Beautiful as the wings of a butterfly, covered by green hills and inspired by the power of the human imagination - that is Kanuma, a cyber world created by scientists. But because Kanuma's self-developing AI began to communicate in a language unknown to humans, engineers want to delete Kanuma. One of the scientists shares the last four hours before it ends with a cyber girl who means a lot to her. Will this friendship last the end of a world?