"Denpa Onna to Seishun Otoko" centers around Makoto Niwa, a high school student who moves to his aunt’s house in the city after his parents relocate overseas for work. His aunt, Meme Touwa, is a carefree and eccentric woman who lives with her daughter, Erio, a mysterious girl who claims to be an alien. Erio spends her days wrapped in a futon, refusing to engage with the outside world, and her behavior has made her a local legend. Makoto, initially skeptical of Erio’s claims, gradually becomes involved in her life, attempting to understand her and help her reintegrate into society.

As the story progresses, Makoto encounters other unique characters, including Ryuuko Mifune, a classmate with a strong sense of justice and a penchant for martial arts, and Maekawa, a quirky girl who works part-time at a local café and often engages in bizarre experiments. These interactions shape Makoto’s experiences as he navigates his new environment and relationships. Erio’s past is slowly revealed, shedding light on her behavior and the reasons behind her alienation. Her journey toward self-acceptance and reconnection with the world forms a central theme of the narrative.

The series blends elements of slice-of-life, comedy, and light science fiction, exploring themes of adolescence, identity, and the search for meaning. Makoto’s pragmatic and grounded personality contrasts with the eccentricities of those around him, creating a dynamic interplay between realism and the surreal. The story maintains a balance between humor and introspection, with moments of absurdity juxtaposed against deeper emotional undertones. Through its exploration of the characters’ struggles and growth, the series offers a nuanced portrayal of youth and the complexities of human relationships.