Her name is Adele.
After the incident, she begins to see a visitor from another world and is admitted to a psychiatric hospital. The doctors are convinced she suffers from hallucinations. The fragments of her consciousness are shattered into pieces. They diagnose her with derealization.

His name is Onisiy.
Where he came from, there is only darkness. For the first time in his existence, this being sees light. Adele becomes a beacon for Onisiy, for she is the only one capable of seeing him. He does not know why he arrived in this world. Now Onisiy learns how it works and studies human society — and humans themselves.