"NEET Kunoichi to Nazeka Dōsei Hajimemashita" centers on the life of Kijima, a young man who unexpectedly finds himself sharing a living space with a kunoichi, or female ninja, named Shion. Shion, a modern-day ninja from a hidden village, is sent to the outside world on a mission but ends up stranded due to her lack of understanding of contemporary society. Kijima, a NEET (Not in Education, Employment, or Training), reluctantly takes her in, leading to a series of comedic and slice-of-life interactions as the two navigate their unconventional cohabitation.

Shion’s lack of familiarity with modern technology and social norms creates frequent misunderstandings and humorous situations. Her ninja training and traditional mindset often clash with Kijima’s laid-back, reclusive lifestyle. Despite their differences, the two gradually develop a bond as they learn to coexist. Shion’s mission remains a recurring element, though the focus primarily lies on the daily life and growing camaraderie between the two characters.

The series explores themes of adaptation, cultural differences, and personal growth, with Shion’s earnestness and Kijima’s gradual opening up to the world around him serving as key narrative drivers. Supporting characters, such as Kijima’s acquaintances and other ninja operatives, occasionally appear to add depth to the story and provide additional comedic or dramatic moments. The dynamic between Shion and Kijima forms the core of the series, blending humor, light-hearted moments, and subtle emotional undertones as they navigate their shared life.