The creator Machiko Kyō, whose name is also written as Kyo Machiko and Kyō Machiko, is a manga artist who began her professional career by drawing one-page comics on her web blog, Sennen Gahō, in 2004. This web series was later compiled into a published book in 2008, marking her formal entry into the publishing industry as a cartoonist. Following this debut, she worked with major publishing houses such as Kōdansha, which released her color slice-of-life series Mikako-san beginning in 2009. Her body of work includes long-form narrative stories, one-page comics, illustrations for books and advertisements, and picture diaries.

Among her most recognized original works is the manga Cocoon, a drama set during World War II that focuses on the experiences of young nurses known as the Himeyuri Student Nurses in the Battle of Okinawa. Another significant work is Mitsuami no Kami-sama, a poetic story created in the aftermath of a major catastrophe, which is rich with allusion to the Fukushima nuclear disaster. She also created the war-themed picture book Ichigo Sensō. In addition to these, she has produced a series of bilingual picture diaries documenting daily life during the COVID-19 pandemic, including Distance My #stayhome Diary and its sequel Essential My #stayhome Diary 2021-2022.

Several of her original works have been adapted into other media. Her manga Cocoon was adapted for the stage by the theater company mum & gypsy. Her award-winning manga Mitsuami no Kami-sama was adapted into an animated short film titled Pigtails for international release, which was produced by the prominent animation studio Production I.G. Regarding these adaptations, Kyō has expressed that she looks forward to seeing the interpretations and worldviews of other artists, which she finds inspiring for her own future creations. She has stated that she loves to watch animation but does not consider it her own profession, as she is more interested in creating a story from scratch and evoking imagination in the reader from a static image.

Recurring themes in Kyō's work often involve juxtaposing elements that seem to be in contrast. Her art is noted for combining a cute or charming visual style with serious, sometimes cruel, subject matter, as seen in the war drama Cocoon. Her work frequently explores women's perspectives, particularly during wartime, and examines concepts of anti-daily life and war heterotopias. She has also repeatedly depicted the motif of a best friend who is close to the heart of the main character. Her artistic style is heavily influenced by the natural environment of the suburbs where she grew up, including rivers and fields. She creates her artwork digitally, often using photographs she has taken as a base, which she then combines, modifies, and recolors extensively, frequently using blue as a foundational color to give the work a sense of warmth.

Machiko Kyō has achieved significant recognition within the manga industry. She won the Tezuka Osamu Cultural Prize's New Artist Prize for Mitsuami no Kami-sama. She also received the Japan Cartoonists Association Award's Grand Prize for her picture book Ichigo Sensō. Her work has been published internationally in countries including Spain, Italy, Taiwan, Vietnam, and Korea. She intentionally keeps her own image out of the public eye to prevent judgments about her appearance from affecting the reception of her work, allowing readers to connect directly with the world she creates.