Makoto Niwa, a high school student, moves to the rural town of Yanomachi to live with his aunt Meme after his mother relocates for work. Upon arrival, he discovers that his cousin, Erio Towa, has become a recluse, wrapping herself in a futon and claiming to be an alien. Erio’s eccentric behavior and her mother Meme’s carefree, unconventional personality create a chaotic household. Makoto, initially overwhelmed, gradually adapts to his new environment and begins to uncover the complexities of his family and the town.

Erio’s belief in her extraterrestrial origins stems from a mysterious incident where she disappeared for six months, only to reappear with no memory of what happened. This event left her socially withdrawn and disconnected from reality. Makoto, though skeptical, becomes involved in her peculiar world, attempting to understand her and help her reintegrate into society. Alongside Erio, Makoto interacts with other unique characters, such as Ryuuko Mifune, a sharp-tongued classmate with a penchant for conspiracy theories, and Maekawa, a quirky girl who often dresses in costumes and shares Erio’s fascination with the unknown.

The narrative explores themes of identity, family, and the blurred line between reality and imagination. As Makoto delves deeper into the lives of those around him, he uncovers hidden truths about Erio’s past and the town’s secrets. The series balances moments of humor and absurdity with poignant reflections on loneliness and self-discovery. Through his interactions with Erio and the other characters, Makoto’s perspective on life and relationships evolves, leading to a deeper understanding of himself and those around him.

The plot unfolds in a nonlinear fashion, blending slice-of-life elements with surreal and fantastical undertones. The series maintains a focus on character development, with each episode revealing new layers to the personalities and motivations of the main cast. The dynamic between Makoto and Erio serves as the emotional core, as their bond grows stronger despite their differences. The story ultimately resolves with a sense of closure, as the characters confront their pasts and embrace their futures, leaving behind the uncertainties that once defined them.